Jaguar XJ6, XJ12 & XJS 1974-77 Brake Repair Manual

Models Covered:

• XJ6
• XJ12
• XJS

DESCRIPTION

Brake system utilizes four wheel disc brakes and a tandem master cylinder connected to  a power unit (servo). Front calipers are four piston type. Master cylinder supplies hydraulic pressure to two individual brake circuits (front and rear). A combination valve is used to indicated a pressure  difference between brake circuits. Front calipers are mounted on stub axle carriers and rear calipers are mounted inbourd on differential housing. Rear rotors are connected to differential drie shaft flanges. Each front caliper consists of four pistons (two inboard and two outboard) and each rear caliper has two opposing pistons. Parking brake consists of independent, lever operated, disc pads mounted on rear calipers. Parking brake pads operate on rear brake rotor.

ADJUSTMENT

DISC BRAKE PADS

Due to self-adjusting feature of calipers, no adjustment in service is required.

PARKING BRAKE

Parking Brake Caliper - Caliper is self-adjusting to compensate for pad wear, therefore no adjustment is required.

Parking Brake Cable - On XJS models only, pull back carpet near rear of drivers seat for access. Put  caliper levers in fully released position. Loosen lock nut and turn adjusting nut until there is a slight amount of slack in cable. Operate brake several times to ensure proper braking has been achieved.

HYDRAULIC SYSTEM BLEEDING

1) Keep hydraulic fluid reservoirs filled with clean brake fluid during bleeding operation. Attach a bleed tube to bleeder screw on left-rear brake caliper, and immerse opposite end of tube in a container partially filled with brake fluid.

2) Run engine at idle speed. Loosen bleeder screw, operate pedal through full stroke until discharged fluid is free of air bubbles, close bleeder screw. Repeat procedure on right-rear caliper and front calipers.

COMBINATION VALVE

Operation Testing - 1) Put gear selector level in park. When ignition switch is on and parking brake is applied, brake warning light should be on. Run engine at idle. Release parking brake. Apply pedal hard.

2) Open any bleeder screw. Brake warning light should light. Close bleeder, then release and reapply brake pedal. Brake warning light should go out. Carefully repeat procedure if warning light will not go on. Replace component as necessary.

REMOVAL & INSTALLATION 

DISC PADS (SERVICE BRAKES)

Removal - Raise vehicle and remove wheels. Remove pin clips, pad retaining pins, anti-chatter springs (if equipped) and lining pads.

Fig. 1 Detail of Parking Brake Caliper

Installation - Draw out about half the brake fluid from reservoir(s). This will enable claiper pistons to be pushed back into cylinders without overflowing fluid. Lever pistons back, insert new pads, springs and replace retaining pins and clips. Check pads for freedom of movement within caliper. Check reservoirs for correct fluid level.

DISC PADS (PARKING BRAKE)

Removal & Installation - Parking brake calipers must be removed to replace disc pads.

PARKING BRAKE CALIPER

Removal - 1) Raise and support vehicle. On XJS models only, adjust some slack into parking brake cable. Remove nuts and bolts attaching rear suspension mounting plate to rear suspension unit and remove plate from vehicle. Disconnect parking brake cable and return spring from caliper

Fig. 2 Components to Remove to Take Off Caliper

2) Remove caliper mounting bolts and release lever, then slide caliper around rotor and remove through hole left by suspension plate. To remove disc pads, remove nut and spring washer pads to pad carriers.

Installation - 1) To install, reverse removal procedure and note the following: On XJ6 and XJ12 models only, adjust caliper if new pads have been installed or if caliper has been  overhauled. Adjust by holding one pad carrier stationary and turning remaining carrier until there is a clearance of .75" (19.0 mm) between disc pad surfaces.

2) On all models, operate caliper actuating lever until adjuster ratchet ceases to click. Install remaining components and check operation of brakes.

NOTE - Do not separate caliper halves for repair. If a leak exist between halves, replace caliper.

Removal (Front) - Raise vehicle and remove wheels. Disconnect caliper fluid line and plug. Discard locking wire from mounting bolts. Remove caliper.

NOTE - Check position and number of shims between steering arm and caliper; replace shims in order.

Installation - 1) Place caliper in position. If original caliper is being reinstalled, refit shims. Install mounting bolts and safety wire. Bleed brakes.

2) If new caliper is being used, check gap between caliper abutment and rotor face. Gap should be no more than .010" (.25 mm). Gap on upper and lower abutment on SAME SIDE must be equal. If rotor is not centered, remove one caliper mounting bolt and add or subtract shims as necessary. Repeat procedure on other bolt.

Removal (Rear) - Remove parking brake caliper as previously outlined. Disconnect and plug hydraulic line from caliper mounting bolts and lock wire. Slide caliper around brake rotor and out hole left by suspension plate.

Installation - Place caliper in position, isntall shims if equipped, and secure bolts. Torque bolts to 49-55 ft. lbs. Check rotor for center between caliper, If necessary, adjust shims between drive flange and rotor. If shim adjustment is performed, rear wheel camber must be checked. Complete installation by reversing removal procedures.

BRAKE ROTOR

Removal (Front) - Remove brake caliper disc pads as previously outlined. Remove hub-to-rotor attaching bolts and washers. Remove hub dust cap, then remove cotter pin, axle nut and washer from axle stub and remove hub. Insert a punch through access hole in splash shield and lightly tap on it to free water deflector. Remove rotor assembly by sliding it from caliper jaws and over axle stub.

Installation (Front) - To install, reverse removal procedure and note the following: Pack hub and wheel bearings with suitable grease and adjust wheel bearing end play. 

Removal (Rear) - Remove brake caliper as previously outlined. Disconnect shock absorber from lower mount and remove radius arm locking bolt and lower control arm outer grease fitting. Place stands under hub assembly and slide radius arm from anchor point. Loosen clamp and side boot away from inner universal joint, then remove universal joint-to-rotor attaching bolts and separate universal joint from rotor.

NOTE - DO NOT move shims mounted between drive axle flange and brake rotor.

Installation - To install, reverse removal procedure and note the following: Ensure caliper is centered on rotor; adjust by adding or removing shims between rotor and drive axle flange. Caliper is centered when gap is not more than .010" (.25 mm). Check rear wheel camber and adjust if necessary.

MASTER CYLINDER

Removal & Installation - Disconnect electrical wires from master cylinder reservoir. Remove filter. Disconnect clips mounted to cylinder. Separate all hydraulic lines and plug openings. Remove nuts mounting cylinder to power unit studs. To install, reverse removal procedure.

POWER BRAKE UNIT (SERVO)

Removal - 1) On XJ6 and XJ12, disconnect battery and remove air cleaner. On all models, disconnect and plug master cylinder lines. Pry vacuum hose from power unit. Remove fluid reservoir.

2) On XJS models, swing pedal box bracket into vertical position. Remove 4 pedal box mounting nuts. Slide off master cylinder. Lift off pedal box and power unit, then separate.

3) On XJ6 and XJ12 models, disconnect choke cable clips. Remove bolt securing upper pedal box. Remove reservoir mounting bracket. Remove stop light switch. Remove 6 bolts attaching pedal box. Remove brake pedal pad. Withdraw pedal box, master cylinder, and power brake unit as an assembly, then separate.

Installation - To install, reverse removal procedure and bleed hydraulic system.

COMBINATION VALVE

Removal & Installation - Disconnect battery. Remove air cleaner. Disconnect electrical lead. Separate fluid lines and plug openings. Remove mounting nut and bolt. To install, reverse removal procedure and bleed brakes.

OVERHAUL

BRAKE CALIPER

Fig. 3 Exploded View of Front Four
Piston Caliper Assembly

NOTE - DO NOT separate caliper halves for service pistons and seals may be changed without  splitting caliper. If a leak is detected between caliper halves, replace caliper as a unit.

Disassembly - With disc pads removed, install a suitable piston clamp to retain outboard piston(s), then apply compressed air to fluid inlet part and remove inboard piston(s). Pull dust seal from piston(s) and caliper grooves. Carefully remove piston seal from cylinder. NOTE - Inboard piston(s) must be installed before outboard piston(s) can be removed.

Cleaning & Inspection - Clean all parts in alcohol and inspect for wear or damage. Check cylinder bore and pistons for scratches, rust or corrosion; replace all damage parts.

Reassembly - Coat cylinder, piston and seal with brake fluid before installing. Place piston seal in bore. Install dust seal cover cylinder groove and carefully insert piston through dust seal. Pull dust seal into groove in piston. Use piston clamp to press piston completely into cylinder. Repeat procedure for outer piston seal replacement. Install caliper as previously outlined.

MASTER CYLINDER

Fig. 4 Exploded View of Rear Brake Caliper With Detail of Parking
Brake Assembly

Disassembly - With master cylinder removed from vehicle, carefully pry hose adaptors from sealing grommets and grommets from master cylinder. Push in primary piston and remove secondary piston

Fig. 5 Exploded View of Dual Piston
Master Cylinder

stop pin from forward grommet housing. Remove spring lock, then tap flange end of cylinder to remove primary and secondary piston assemblies. Disassemble springs, spring seats, seals and washers from piston assemblies.

Cleaning & Inspection - Clean all parts in alcohol and dry with a lint-free cloth. Inspect pistons and bore for wear, scores, or corrosion; replace damaged parts as necessary.

Reassembly - To reassemble, reverse disassembly procedure and not the following: Lubricate all parts with clean brake fluid. Install secondary piston inner seal with lip facing away from primary piston and install outer seal with lip facing primary piston. Install primary piston seal with lip facing away from spring lock. Install master cylinder and bleed brake system.

COMBINATION VALVE

NOTE - Combination valve CANNOT be overhauled

POWER BRAKE UNIT (SERVO)

NOTE - Power brake unit CANNOT be overhauled; if determined defective, replace entire unit.

Jaguar 420, XKE, XJ6 and XJ12 1967-73 Brake Repair Guide

Models Covered:

• 420 & 420 G (1967)
• XKE (1965 - 71)
• XJ6 Sedan (1970-73)
• XJ12 Sedan (1971-73)

DESCRIPTION

XJ6 &XJ12 

Brake system utilizes four wheel disc brakes and a tandem master cylinder connected to a power servo unit. Master cylinder provides separate hydraulic circuits for front and rear brake calipers. Front calipers are mounted on stub axle carriers and rear calipers are mounted inboard on differential housing, with rotor connected to differential drive flanges. Each front caliper consist of three pistons (two outboard, one inboard), and each rear caliper consists of two opposing pistons. Parking brake consists of independent lever-operated calipers mounted on service brake calipers. Parking brake calipers operate on service brake rotors.

420 & XKE

Brake system utilizes four wheel disc brakes. Master cylinder is combined with a booster reaction valve, actuating a tandem piston slave cylinder connected to a booster servo. Each cylinder employs a separate hydraulic fluid reservoir. Master cylinder is actuated by pedal linkage and slave cylinder is operated by servo. Slave cylinder contains two separate hydraulic circuits actuating front and rear brake calipers. Front calipers, mounted on steering arms, consist of three pistons (two outboard, one inboard). Rear calipers, mounted on differential housing consist of two opposing pistons, and operate on rotors connected to differential output flanges. Parking brake consists of two separate lever operated calipers mounted on service brake calipers. Parking brake calipers operate on service brake rotors.

ADJUSTMENT

DISC BRAKE PADS

Due to self-adjusting feature of calipers, no adjustment in service is required.

PARKING BRAKE

Parking Brake Caliper - Caliper is self-adjusting to compensate for pad wear, therefore, no adjustment is required.

Parking Brake Cable (XJ6 & XJ 12) - Fully release lever. Loosen front yoke lock nut, and remove clevis pin securing yoke to bell crank lever. Ensure calipers are fully released. Turn back yoke on adjuster rod so a slight amount of slack is present when yoke is connected to lever. CAUTION - Binding may result if all slack is removed from cable. Connect yoke to lever, secure with clevis pin, and tighten lock nut.

Parking Brake Cable (420 & XKE) - Fully release parking brake lever. Loosen lock nut at rear of cable. Screw out threaded adapter until parking brake operating lever starts to move. Loosen adapter one-half turn and tighten lock nut. CAUTION - Do not remove all slack from cable because binding may result.

HYDRAULIC SYSTEM BLEEDING

Keep hydraulic fluid reservoirs filled with clean brake fluid during bleeding operation. Attach a bleed tube to bleeder screw on left-reaer brake caliper, and immerse opposite end of tube in a container partially filled with brake fluid. NOTE - On XKE, remove rear seat for access to rear brake caliper bleeder screws. Loosen bleeder screw, operate pedal through full stroke until discharged fluid is free of ai bubbles, and close bleeder screw. Repeat procedure on right-rear caliper and front calipers. Refill brake fluid reservoirs and check system for leaks

REMOVAL & INSTALLATION

DISC PADS (SERVICE BRAKES)

NOTE - Following procedure is used to remove disc pads from all four wheels on all vehicles, except rear pads on XKE.

Removal (All Exc. XKE Rear) - Raise vehicle and remove wheels. Remove pin clips, pad retaining pins, anti-chatter springs (if equipped) and lining pads.

Installation - Draw out about half the brake fluid from reservoir(s). This will enable caliper pistons to be pushed back into cylinders without overflowing fluid. Lever pistons back insert new pads, springs and replace retaining pins and clips. Check pads for freedom of movement within caliper. Check reservoirs for correct fluid level.

Removal (XKE Rear) - Remove rear seat cushion on both caliper inspection covers for access to rear calipers. Remove clips retaining pins, and withdraw pads.

Installation - Draw out half the reservoir fluid if pistons are to be pushed back within cylinders. Install new pads, pins, and clips. Clean old sealer from inspection covers and apply suitable waterproof sealer. Instal new gaskets and secure bolts. Replace seat cushion and check reservoir fluid leve. 

DISC PADS (PARKING BRAKE)

Removal (All Exc. XKE) - Disconnect hand brake cable levers from hand brake pad carriers. Remove bolts holding carrier refraction plate. Remove hand brake pad carrier rearwards around rotor and withdraw from suspension crossmember. Remove old pads by loosening nuts on outer face of carrier and lifting out with a suitable hook tool.

Installation - Install new pads, short face up and check retaining bolts for fit in pads. Install a new retraction plate and reassemble carrier to main caliper, but do not tighten bolts. Pull and release hand brake lever until ratchet stops. With hand brake lever pulled reasonably hard, tighten carrier pivot bolts and secure locking tabs. Reconnect hand brake linkage and check adjustment.

Removal (XKE) - Remove rear suspension unit. With suspension system removed, lift pivot bolt lock tabs, remove bolts and retraction plate. Withdraw pad carriers through top of suspension unit crossmember. Remove pad clamp bolts and pads.

Isntallation - Wind pad carrier out along adjuster bold two or three turns. Use new clamp bolts, nuts and washers to ensure new pads. Wind carrier along adjuster bolt to give dimension of 750" (19.05 mm) between pad faces. Place pad carriers in position on caliper. Install retraction plate with tips in pad carrier. Secure pad carrier with bolts and tab washers. Move operating lever back and forth until ratchet stops. This set pads to correct clearance. Reinstall suspension system, connect fluid line, hand brake cable and bleed brakes.

FRONT CALIPER LINING
REPLACEMENT

REMOVAL & INSTALLATION

BRAKE CALIPER

NOTE - Do not separate caliper halves fro repair, if a leak exist between halves, replace caliper.

Removal (Front) - Raise vehicle and remove wheels. Disconnect caliper fluid line and plug. Discard locking wire from mounting bolts, remove nuts and caliper. NOTE - Check position and number of shims between steering arm and caliper, if equipped with shims replace in same order.

Installation - Place caliper in position, install shims, if equipped, secure bolts and lock with wire. Connect fluid line and bleed brakes.

Removal (Rear) - Remove rear suspension unit. With rear suspension removed, remove hand brake carrier as previously outlined. Remove brake fluid line from caliper and plug end. Remove pads, caliper retaining bolts and caliper through front opening in

XKE REAR CALIPER LINING
REPLACEMENT
(REAR SEAT REMOVED)

crossmember.

Installation - Place caliper in position, install shims if equipped and secure bolts. Torque bolts to 49-55 ft. lbs. Check rotor for center between caliper. If necessary, adjust shims between drive flange and  rotor. If shim adjustment is performed, rear wheel camber must be checked. Complete installation by reversing removal procedures.

BRAKE ROTOR

Removal (Front) - Remove caliper as previously outlined. Remove hub grease cap and cotter pin. Cotter pin is removed through hole provided in hub on vehicles with wire wheels. Remove slotted nut, washer and hub with rotor attached. Remove set screw (pressed wheels) or bolts (knock off wheels) separating rotor from hub. NOTE - Discard self-locking nuts used with "Knock Off Wheels", install new hub to rotor lock nuts.

Installation - Mount rotor to hub pack bearings with suitable grease and install hub fasteners. Set hub end play within specification and check rotor runout. Install caliper and bleed brakes.

Removal (Rear) - Rear suspension system must be removed in order to remove claipers and rotors. With suspension system removed, remove brake caliper as previously outlined. Invert suspension unit and remove shock absorber and spring assembly. Release clips from universal joint shield (if equipped) and slide back. Remove fasteners securing half shaft inner universal joint and brake rotor to differential shaft flange. Withdraw half shaft from bolts. NOTE - Check number and position of camber shims between universal joint and rotor to differential joint and rotor. Tap brake rotor securing bolts back as far as possible. Lift lower control arm, hub carrier and half shaft assembly upward until brake rotor can be withdrawn.

Installation - Position rotor against differential shaft flange and top through bolts. Reinstall same camber shims removed during disassembly on flange bolts. Secure half shaft universal joint flange to differential flange using four new self-locking nuts. Check brake rotor runout, limit is .006" (.15 mm). Reinstall universal joint shield, springs, shock absorber, and caliper. Use feeler gauges to check rotor for center between caliper halves. If necessary to recenter rotor, remove caliper, rotor and place required shims between drive flange and rotor. Reinstall rear suspension system, check rear wheel camber and adjust if necessary.

MASTER CYLINDER

Removal & Installation (XJ6 & XJ12) - Drain brake fluid reservoir, disconnect hydraulic lines and mark location for reassembly reference. Remove nuts and washers retaining cylinder to servo unit, remove vacuum line retaining strap, and separate cylinder from servo. To install, reverse removal procedure and bleed hydraulic system.

Removal (XKE) - Disconnect battery and remove left hand air cleaner. With Manual Transmission, remove nut securing brake master cylinder and clutch reservoir. With Automatic Transmission, remove fastener retaining reservoir. Drain fluid from master cylinder reservoir, disconnect line fitting from master cylinder and temporarily reinstall bolt to retain valve trap assembly in outlet port. Remove window washer reservoir. Loosen connector nearest to servo vacuum shell and remove fluid line clear of brake master cylinder. Loosen line clips securing air lines to reaction valve and remove lines. Remove nuts securing master cylinder to pedal box studs. Withdraw master cylinder from studs leaving push rod attached to pedal.

Removal & Installation (Model 420) - Drain master cylinder reservoir fluid, disconnect two vacuum hoses from reaction valve and two fluid lines from master cylinder. Remove brake pedal clevis and push rod. Remove fasteners with master cylinder from pedal housing. To install, reverse removal procedure, use new copper washer on fittings and bleed brakes.

Installation - Reverse removal procedure and note the following: Install new copper gaskets on fluid line fittings. Check brake pedal for free travel, .125" (3.17 mm), before resistance of master cylinder piston is felt. Adjust with lock nut on push rod. Check brake light switch for proper operation.

SERVO ASSEMBLY

Removal & Installation (XJ6 & XJ12) - Remove right air cleaner and disconnect choke cable from right-front carburetor. Disconnect hydraulic lines and vacuum line. Disconnect electrical leads from fluid level warning switch. Remove reservoir and bracket assembly from pedal box. Remove nuts securing pedal box vertical mounting to firewall, lift heater vacuum pipe cleaer of studs, remove brake light switch and remove bolts securing pedal box base mounting to firewall. Lift out pedal box, servo unit and master cylinder on assembly. Remove nuts securing servo to pedal box, remove rubber sealing plugs and remove clevis pin connecting servo operating rod to brake pedal lever. To install, reverse removal procedure and bleed hydraulic system.

Removal & Installation (XKE) - Disconnect battery, remove reservoir tank, window washer reservoir and bracket. Remove slave cylinder reservoir and left hand air cleaner. Remove fluid line from master cylinder outlet and replace bolt. Remove fuel line clip and pull off flex hose. Disconnect vacuum hoses from servo. Remove nuts securing brake master cylinder to pedal box. Withdraw master cylinder from mounting and tie to one side. Disconnect fluid lines on slave cylinder and plug ends. Remove fluid feed hose from top of slave cylinder. Inside vehicle, pull carpet from left hand front floor panel. Remove fasteners from slave cylinder bracket and remove servo. To install, reverse removal procedure and bleed brake system.

Removal & Installation (Model 420) - Drain slave cylinder reservoir, jack up vehicle front and remove left wheel. Remove fiberglass cover to servo unit and mounting bracket. Disconnect three hoses and line fittings from servo and slave cylinder. Seal open ends of hoses and lines to prevent entry of dirt. Remove four set-screws securing servo mounting bracket to inner panel and withdraw assembly. Separate servo from mounting bracket for unit service. To install, reverse removal procedure.

OVERHAUL

REAR CALIPER & PARKING BRAKE ASSEMBLY

BRAKE CALIPER

NOTE - DO NOT separate caliper halves for service, pistons and seals may be changed without splitting caliper. If a leak detected between caliper halves, replace caliper as a unit.

FRONT CALIPER COMPONENTS 

Disassembly (All Models) - With disc pads removed, install a piston clamp to retain outboard piston(s), then apply compressed air to fluid inlet and remove inboard piston. Pull dust seal from piston and caliper grooves. Carefully remove piston seal from cylinder. Remove outboard piston(s) and seal in same manner.

Cleaning & Inspection - Clean all parts in alcohol and inspect for wear or damage. Check cylinder bore and pistons for scratches, rust or corrosion; replace all damaged parts.

Reassembly - Cot cylinder, piston and seal with brake fluid before installing. Place piston seal in bore. Install dust seal over cylinder groove and carefully insert piston through dust seal. Pull dust seal into groove in piston. Use piston clamp to press piston completely into cylinder. Repeat procedure for outer piston seal replacement. Install caliper as previously outlined.

MASTER CYLINDER ASSEMBLY (XJ6 & XJ12)

MASTER CYLINDER

Disassembly (XJ6 & XJ12) - Remove tipping valve cover, seal, and retaining nut. Depress primary piston and remove tipping valve. Withdraw primary piston, spring, and secondary piston assembly. Compress secondary piston spring and lift spring retainer leaf. Remove valve, waved washer, spacer, spring and thimble. Remove seals from valve head, and primary and secondary pistons.

MASTER CYLINDER & REACTION VALVE (XKE)

Cleaning & Inspection - Clean all parts in alcohol and dry with a lin free cloth. Inspect pistons and bore for wear, scores, or corrosion; replace damaged parts as necessary.

Reassembly - Lubricate all parts with clean brake fluid, reverse disassembly procedure and note the following: Install seal on primary piston with groove facing forward. Install valve seal with smallest diameter leading onto valve head.

Disassembly (XKE - 1) Remove bolts, fittings, and valve trap assembly from top of cylinder. Remove dust boot, compress piston return spring and remove spring retainer. Press piston into bore, remove snap ring using special snap ring pliers (7066), and remove piston asssembly, spring, spring retainer and lever. NOTE - Bearing "O" ring seal may expand into snap ring groove making removal difficult. If necessary, wrap jaws of pliers with tape and use to extract piston assembly.

2) Remove bearing "O" ring seal, and secondary cup assembly from piston. Remove plastic spring retainer. NOTE - Retainer is a press fit on piston and requires firm force against its back to remove. Remove main cup and piston washer. Remove reaction valve assembly from cylinder body. Remove valve piston by inserting a screwdriver into fluid line outlet port. Move valve along its bore until it can be removed by hand. Remove "O" ring and seal from piston.

Cleaning & Inspection - Wash all components in alcohol and inspect for scoring, pitting, or wear. Replace all damaged parts. Before assembly, coat "O" ring seals and plastic bearings with disc brake lubricant.

Reassembly - Coat all parts with clean brake fluid, reverse disassembly procedure, and note the following: When installing piston lever, make sure lever tab drops into recess when lever reaches bottom of cylinder bore. If necessary, press reaction valve piston forward with a blunt screwdriver fed through fluid outlet port.

Jaguar XJ6 XJ12 XJS 1975-77 Drive Axles Repair Manual

DESCRIPTION 

The differential assembly is of hypoid design with centerline of drive pinion gear set below centerline of ring gear. A collapsible spaer is used to set drive pinion bearing preload and all other differential adjustments are accomplished using shims. Stub axles transmit power out of differential, through independent rear suspension, to drive wheels. A clutch pack limited slip unit, "Powr-Lok", is available as an option.

AXLE RATIO AND IDENTIFICATION

Jaguar uses only one basic rear axle design, however, unit may not be fitted with a traction lock device. Also several different axle ratios are used. To determine axle ratio, divide number of ring gear teeth by number of pinion gear teeth. Whether or not axle is fitted with traction lock should be determined owner inquiry or test.

REMOVAL AND INSTALLATION

Rear Suspension Assembly

NOTE - This procedure is provided since many operations on the final drive require removal of rear suspension assembly before starting work on final drive.

1) Raise and support vehicle. Place stands forward of radius arms on body with wood blocks between body and stands. Remove wheels. Remove mufflers from tail pipes. Remove safety wire and bolts securing safety strap and radius arm from body mounting post. Disconnect and plug brake lines at body.

2) Remove clevis pin securing hand brake cable to actuating levers on crossmember. Loosen lock nut and remove outer hand brake cable screw from adjuster block. Detach drive shaft from differential. Place jack under rear suspension. Remove bolts and lock nuts securing crossmember mounts to frame. Lower and remove rear suspension from vehicle. To install, reverse removal procedure and note the following. Bleed brakes. Tighten radius arm nuts on lower control arm when weight of vehicle is on wheels.

HALF SHAFT

1) Remove rear suspension assembly. Remove rear hub as follows: Remove fulcrum shaft grease fitting. Withdraw cotter pin and remove nut and washers from splined end of half shaft. Using suitable puller, pull hub and carrier from half shaft. Remove spacer from half shaft and examine inner oil seal track. Replace track if necessary. Remove one nut from outer suspension arm fulcrum shaft and using soft hammer, drift out shaft. Remove hub and carrier assembly from car.

2) Support suspension arm with jack and remove nut and bolt securing top of forward shock absorber. Remove nuts and washer securing shock absorber to suspension arm and remove shock. Remove four nuts securing half shaft flange to stub axle flange and brake rotor. Pull half shaft from suspension unit noting number of camber shims installed between half shaft flange and brake rotor. If necessary, remove joint shields by drilling out rivets.

3) To install, reverse removal procedure, noting the following if necessary, replace joint shield, positioning grease nipple access hole correctly. Cover joint lines in shield with non hardening waterproof sealing compound. Be sure to replace camber shims. To reinstall rear hub, proceed as follows: Install suitable dummy shaft (JD.14) in hub carrier fulcrum. Install carrier on suspension arm, installing shims removed from between carrier and suspension arm. Replace outer suspension arm fulcrum shaft, displacing dummy shaft. Secure shaft with nut and reinstall grease nipple.

Fig. 1 Exploded view of Jaguar "Power-Lok" Differential Assembly

4) If necessary, install oil seal track to half shaft splined flange, replace spacer. Thoroughly clean and de-grease splines of half shaft and bore of hub. Using a small brush sparingly apply Lactite "Stud Lock" to outer two thirds of half shaft splines. Assemble hub carrier to half shaft. Install washer and tighten hub carrier assembly nut. Install new cotter pin. Install dial indicator so it bears against hub and zero indicator. Using two levers, pry out on hub and measure hub bearing endfloat. If endfloat exceeds specifications, overhaul rear hub and carrier assembly. After installation of rear suspension in vehicle, check rear wheel camber.

STUB AXLE OIL SEAL

1) Remove half shaft. Remove locking wire and withdraw bolts securing brake caliper to final drive unit. Remove brake rotor, noting number of shims removed between rotor and stub axle flange. Remove lock wire and five bolts securing caliper mounting bracket. Withdraw drive shaft, together with caliper mounting shims, ball bearing and oil seal. Turn down tab washer and remove nut nut from stub axle. Remove ball bearing and caliper mounting bracket from stub axle.
2) Lightly oil seal and position carefully in final drive case. Press seal squarely and fully seat in case groove. Do NOT remove protruding portion of seal. Coat seal with hypoid oil and place caliper mounting bracket and seal assembly over stub axle. Slide ball bearing on drive shaft followed by new tab washer and nut. Ensure bearing seats square to stub axle shoulder and tighten nut. Turn up tab on washer.
3) Lightly oil stub axle splines and install shaft in final drive housing. Install bolts securing mounting bracket finger tight. Using feeler gauge, measure dimension between inside face of mounting bracket and final drive housing. The measurement obtained determines shim thickness required, and thinly coat mating faces and shims with suitable sealant (Hylomar). Tighten bolts in a diagonal sequence.
4) Wire lock securing bolts to tension in clockwise direction. Install brake rotors and half shaft flange, using shims removed from between rotor and flange. Install caliper on mounting bracket. Install suitable distance spacers (oversize nuts) to rotor studs and tighten nuts. Use feeler gauges to ensure that rotor is centrally located between jaws of caliper. If necessary add to or remove from shim pack between flange and disc to center rotor. Continue assembly in reverse of disassembly procedure.

PINION FLANGE AND SEAL

1) Disconnect propeller shaft. Check and record torque required to turn drive shaft flange clockwise (viewed from front) through backlash movement. Check rear wheels and remove flange securing nut and washer. Remove flange. Pry oil seal out of final drive case. Lightly score oil seal recess with tang of file.
2) Ensure oil seal recess is clean and free of oil. Lightly top new oil seal into recess ensuring seal is square with case. Reinstall flange, washer and nut. Tighten nut to 120 ft. lbs. (16.5 mkg) while rotating flange to ensure bearing seats correctly. Again check pinion preload. If preload is below specifications, continue tightening flange nut until specified preload is obtained. However, if preload exceeds maximum specified value, new collapsible spacer must be installed, see differential overhaul. Reconnect propeller shaft and remove wheel chocks.

FINAL DRIVE UNIT

1) Remove rear suspension assembly and drain final drive unit. Remove final drive mounting plate and shock absorber/spring units. Remove nuts securing half shaft inner universal joint to brake rotor and disconnect half shaft, noting shims removed. Remove nut from inner suspension arm fulcrum shaft and drift out shaft. Repeat for other side of unit. Disconnect and plug brake lines. Disconnect hand brake levers from compensator.
2) Remove locking wire from final drive mounting bolts, remove bolts and crossmember by tilting forward over pinion. Remove calipers from final drive unit. Remove brake rotors, noting number of shims removed from between rotor and stub axle flange. To install, reverse removal procedure  making sure brake rotor is centered between jaws of caliper and wire lock tension bolts in clockwise direction.

OVERHAUL

Fig. 2 Exploded View of Limited Slip
Differential Clutch Pack and Side
and Pinion Gears

1) Remove rear cover and discard gasket. Remove lock wire and bolts securing caliper mounting bracket. Withdraw stub axle along with caliper mounting brracket shims, ball bearing and oil seal. Turn down tab washer and remove nut, ball bearing and caliper mounting bracket from stub axle. Repeat procedure fro second stub axle. Remove bolts securing differential bearing caps and lift off caps. Pry out differential assembly using two levers and taking care not to damage housing.
2) Remove drive pinion nut and washer. Mark relative positions of flange and pinion and remove flange. Using a suitable press, remove pinion from differential housing. Remove oil seal, oil thrower and outer bearing cone. Examine inner and outer bearing cups fro wear. If replacement is required, extract cups using suitable tools (SL.14 and SL. 14/1). NOTE - If removal of bearing cups is difficult, gently heat final drive housing in rear of bearing caps. On "Powr-Lok" differentials only, proceed as follows:
3) Remove differential side bearings using suitable tools (SL.14 and 14/3). If no reference marks are present, scribe a line across both halves of differential case to ensure correct reassembly. Remove bolts securing both halves of differential case. Split case and remove clutch discs and plates from one side. Remove differential side ring, pinion side gear and pinion cross shafts complete with gears. Remove remaining side gear and ring and extract remaining clutch discs and plates.
4) On non "Powr-Lok" differential only, remove peening and drift pinion shaft lock pin out of carrier. Remove gears, shaft and shims from carrier.

REASSEMBLY AND ADJUSTMENT

 Fig. 3 Measuring Side Bearing Preload

Case Assembly - 1) On "Powr-Lok" differentials, install clutch plates and disc alternately into flange half of case. Installtwo belleville clutch plates so that convex sides are against case. Install side ring and position one side gear into ring recess. Install cross shafts. Install pinion cross shafts complete with pinion gears ensuring that ramps on shafts coincide with mating ramps in case.
2) Assemble differential case halves ensuring that reference marks are lined up and clutch friction plate tongues are aligned with grooves in differential case. Install bolts but do not tighten yet. Check alignment of splines by inserting both stub axles. Tighten differential case bolts with stub axles in position. With one stub axle locked, other axle must not turn more than .75" (19 mm) measured on a 6" (152 mm) radius.
3) On non "Powr-Lok" differentials, install pinion shaft, shims and gears into differential carrier. Secure lock pin by peening.
Side Bearing Preload - Install differential side bearing without shims, on differential case, making sure that bearing and housing are perfectly clean. Place differential assembly in housing. Install dial indicator with indicator leg against back face of ring gear. Using sutiable pry bars between housing and bearing cups, move differential assembly fully to one side of housing. Zero dial indicator and move assembly to other side. Record indicator reading and add .009" (.20 mm) to reading to give total shim pack required. Remove differential assembly from housing.

Fig. 4 Measuring Drive Pinion
Gear Installed Depth

Drive Pinion Depth - 1) Place pinion, together with inner bearing cone, into housing. Turn housing over and support pinion. Install pinion outer bearing cone, flange, washer and nut, omitting collapsible spacer, oil slinger and oil seal, tighten nut. Using suitable dial indicator support fixture (SL3), zero dial indicator on setting block (4.H.A.). Place dial indicator fixture firmly on face of pinion and not indicator reading to bottom of housing bearing bore (see illustration).
2) The indicator reading shows deviation of pinion setting from zero cone setting. This value agree with value etched on face of pinion at bottom. For example, if value etched on pinion is -2, dial indicator should read -.002". If setting is incorrect, dismantle pinion and remove pinion inner bearing cup. Add or remove shims as required, reassemble and recheck pinion depth.
3) When setting is correct, extract pinion fro housing sufficiently far to remove outer bearing cone. Install collapsible spacer to pinion ensuring that it seats firmly on machined shoulder of pinion. Insert pinion into housing, install outer bearing cone, oil slinger and oil seal. Lightly grease splines of pinion shaft and install flange. Install new washer on end of pinion with convex side facing end of shat. Install but DO NOT tighten nut.
Backlash Adjustment - 1) Place differential assembly complete with side bearings but less shims, in housing. Ensure that bearings and housing are perfectly clean. Install dial indicator on housing with feeler on back face of ring gear. Pry differential case and ring gear assembly away from pinion until opposite side bearing is seated against housing. Zero dial indicator at this point.
2) Move differential assembly towards pinion until ring gear is deeply meshed with pinion. Note indicator reading and from this value, subtract the backlash allowance etched on drive gear (eg B/L.007 dones .007"). This result will yield the thickness of shims (in inches) to be placed between differential case and side bearing on ring gear side of differential. Install this thickness of shims (in inches) to be placed between differential case and side bearing on ring gear side of differential. Install this thickness of shims, taking shims from pack determined previously under "Side Bearing Preload". Install balance of total shims required on opposite side of case. An example of calculations required follows
EXAMPLE:

Fig. 5 Measuring to Determine Ring Gear
Side Shim Thickness

     Side Bearing Preload Reading.....................  .080"
     PLUS Preload Value.................................   .009"
     Total Shim Pack.......................................  .089"

     Pinion-to-Ring Gear Clearance...................  .042"
     MINUS Etched Backlash Value..................  .007"
     Total Ring Gear Side Shims.......................  .035"

     Total Shim Pack.......................................  .089"
     MINUS Ring Gear Side Shims...................  .035"
     Opposite Ring Gear Shim Pack..................  .050"
3) With shims calculated installed, lower differential assembly into position, lightly tapping bearings home with a soft hammer. Make sure ring and pinion gears mesh as installation proceeds. Install side bearing cups, ensure proper cup is placed in proper bearing. Tighten cup bolts. Mount dial indicator on housing with feeler against back face of ring gear. Turn pinion by hand and check ring gear run out. If run out exceeds specifications, disassemble differential, clean all mounting surfaces and check for burns.

Fig. 6 Measuring  Ring Gear-to-Drive Pinion
Gear  Backlash

4) Now place dial indicator to measure ring gear backlash. Move ring gear and check that backlash is to specifications, transfer necessary shims from side of differential case to the other. NOTE - To increase backlash, remove shims from ring gear side and install on opposite side and vise versa. Finally run a gear tooth contact pattern and adjust shims as necessary.
Pinion Bearing Preload - Install pinion and stub axle of seals. Install stub axles following procedure given under stub axle removal and installation. Tighten flange nut to specified torque. During tightening process rotate flange to ensure correct seating of taper roller bearings. Use care not to over tighten nut. if nut is overtightened, install a new collapsible spacer as pinion bearing preload will otherwise be incorrect. Install final drive rear cover using new gasket and suitable sealer (Hylomar).

Jaguar 1968-74 Drive Axles Repair Manual

MODELS COVERED

• XJ6 (1969-74)
• XJ12 (1973-74)
• XKE 4.2 Liter (1968-71)
• XKE V12 (1971-74)

DESCRIPTION

Rear axles are hypoid design with center line of pinion set below centerline of ring gear, Jaguar uses, as standard equipment on XKE models and optional equipment on XJ models, a traction lock or "Powr-Lok" differential which utilizes, clutch discs and plates. All differential adjustments are performed  using shims. As independent rear suspension is utilized on all models, stub axles are used for drive output. These stub axles require a shim adjustment also. A collapsible spacer is used on drive pinion shaft.

AXLE RATIO AND IDENTIFICATION

Jaguar uses only one basic rear axle design, however, unit may or may not be fitted with a traction lock device. Also several different axle ratios are used. To determine axle ratio divide number of ring gear teeth by number of pinion gear teeth. Whether or not axle is fitted with traction lock should be determine by owner inquiry or not.

REMOVAL AND INSTALLATION

Rear Suspension Assembly

NOTE - This procedure is provide since may operation on the final drive require removal of rear suspension assembly before starting work or final drive.

1) Raise and support vehicle. Place stands forward of radius arms on body with wood blocks between body and stands. Remove wheels. Remove mufflers from tail pipes. Remove safety wire and bolts securing safety strap to body. Remove radius arm securing bolt, safety strap and radius arm from body mounting post. Disconnect and plug brake lines of body.

2) Remove clevis pin securing hand brake cable to actuating levers on crossmember. Loosen lock nut and remove outer hand brake cable screw from adjuster block. Detach drive shaft from differential. Place jack under rear suspension. Remove bolts and lock nuts securing crossmember mounts to frame. Lower and remove rear suspension from vehicle. To install, reverse removal procedure and note the following: Bleed brakes. Tighten radius arm nuts on lower control arm when weight of vehicle is on wheels.

HALF SHAFT

1) Remove rear suspension assembly. Remove rear hub as follows: Remove fulcrum shaft grease fitting. Withdraw cotter pin and remove nut and washers from splined end of half shaft. Using suitable puller, pull hub and carrier from half shaft. Remove spacer from half shaft and examine inner oil seal track. Replace track if necessary. Remove one nut from outer suspension arm fulcrum shaft and using soft hammer, drift out shaft. Remove hub and carrier assembly from car.

2) Support suspension arm with jack and remove nut and bolt securing top of forward shock absorber. Remove nuts and washer securing shock absorber to suspension arm and remove shock. Remove four nuts securing half shaft flange to stub axle flange and brake rotor. Pull half shaft from suspension unit noting number of camber shims installed between half shaft flange and brake rotor. If necessary, remove joint shields by drilling out rivets.

3) To install, reverse removal procedure, noting the following: If necessary, replace joint shield, positioning grease nipple access hole correctly. Cover joint lines in shield with non-hardening waterproof sealing compound. Be sure to replace camber shims. To reinstall rear hub, proceed as follows: Install suitable dummy shaft (JD.14) in hub carrier fulcrum. Install carrier and suspension arm. Replace outer suspension arm fulcrum shaft, displacing dummy shaft. Secure shaft with nut and reinstall grease nipple.

4) If necessary, install oil seal track to half shaft splined flange, replace spacer. Thoroughly clean and de-grease splines of half shaft and bore of hub. Using a small brush, sparingly apply Lactite "Stud Lock" to outer two thirds of half shaft splines. Assemble hub carrier to half shaft. Install washer and tighten hub carrier assembly nut. Install new  cotter pin. Install dial indicator so it bears against hub and zero indicator. Using two levers, pry out on hub and measur hub bearing endfloat. If endfloat exceeds specifications, overhaul rear hub and carrier assembly. After installation of rear suspension in vehicle, check rear wheel camber.

STUB AXLE OIL SEAL

1) Remove half shaft. Remove locking wire and withdraw bolts securing brake caliper to final drive unit. Remove brake rotor, noting number of shims removed between rotor and stub axle flange. Remove lock wire and five bolts securing caliper mounting bracket. Withdraw drive shaft, together with caliper mounting shims, ball bearing and oil seal. Turn down tab washer and remove nut from stub axle. Remove ball bearing and caliper mounting bracket stub axle.

2) Lightly oil new seal and position carefully in final drive case. Press seal squarely and fully seat in case groove. Do NOT remove protruding portion of seal. Coat seal with hypoid oil and place caliper mounting bracket and seal assembly over stub axle. Slide ball bearing on drive shaft followed by new tab washer and nut. Ensure bearing seats square to stub axle shoulder and tighten nut. Turn up tab on washer.

3) Lightly oil stub axle splines and install shaft in final drive housing. Install bolts securing mounting bracket finger tight. Using feeler gauges, measure dimension between inside face of mounting bracket and final drive housing. The measurement obtained determines shim thickness required. Remove stub axle and select shims of required thickness, and thinly coat mating faces and shims with suitable sealant (Hylomar). Tighten bolts in a diagonal sequence.

4) Wire lock securing bolts to tension in clockwise direction. Install brake rotors and half shaft flange, using shims removed from between rotor and flange. Install caliper on mounting bracket. Install suitable distance spacers (oversize nuts) to rotor studs and tighten nuts. Use feeler gauge to ensure that rotor is centrally located between jaws of caliper. If necessary add to or remove from shim pack between flange and disc to center rotor. Continue assembly in reverse of disassembly procedure.

PINION FLANGE AND SEAL

1) Disconnect propeller shaft. Check and record torque required to turn drive shaft falnge clockwise (viewed from front) through backlash movement. Chock rear wheels and remove flange securing nut and washer. Remove flange. Pry oil seal out of final drive case. Lightly score oil seal recess with tang of file.

2) Ensure oil seal recess is clean and free of oil. Lightly top new oil seal into recess ensuring seal is square with case. Reinstall falnge, washer and nut. Tighten nut to 120 ft. lbs. (16.5 mkg) while rotating flange to ensure bearing seats correctly. Again check pinion preload. If preload is below specifications, continue tightening flange nut until specified preload is obtained. However, if preload exceeds maximum specified value, new collapsible spacer must be installed, see differential overhaul. Reconnect shaft and remove wheel chocks.

FINAL DRIVE UNIT

1) Remove rear suspension assembly and drain final drive unit. Remove final drive mounting plate and shock absorber/spring units. Remove nuts securing half shaft inner universal joint to brake rotor and disconnect half shaft, noting shims removed. Remove nut from inner suspension arm fulcrum shaft and drift out shaft. Repeat for other side of unit. Disconnect and plug brake lines. Disconnect hand brake levers from compensator.

2) Remove locking wire from final drive mouting bolts, remove bolts and crossmember by tilting forward over pinion. Remove calipers from final drive unit. Remove brake rotors, noting number of shims removed from between rotor and stub axle flange. To install, reverse removal procedure making sure brake rotor is centered between jaws of caliper and wire lock tension bolts in clockwise direction.

OVERHAUL

Disassembly

1) Remove rear cover and discard gasket. Remove lock wire and bolts securing caliper mounting braket. Withdraw stub axle along with caliper mounting bracket shims, ball bearing and oil seal. Turn down tab washer and remove nut, ball bearing and caliper mounting bracket from stub axle. Repeat procedure for second stub axle. Remove bolts securing differential bearing caps and lift off caps. Pry out differential assembly using two levers and taking care not to damage housing.

2) Remove drive pinion nut and washer. Mark relative positions of flange and pinion and remove flange. Using a suitable press, remove pinion from differential housing. Remove oil seal, oil thrower and outer bearing cone. Examine inner and outer bearing cups for wear. If replacement is required, extract cups, using suitable tools (SL 14 and SL 14/1). NOTE - If removal of bearing cups is difficult, gently heat final drive housing in rear of bearing cups. On "Powr-Lok" differentials only, proceed as follows.

3) Remove differential side beaings using suitable tools (SL. 14 & 14/3). If no reference marks are present, scribe a line across both halves of differential case to ensure correct reassembly. Remove bolts securing bolts halves of differential case. Split case and remove clutch discs and plates from one side. Remove differential side ring, pinion side gear and pinion cross shafts complete with gears. Remove remainin side gear and ring and extract remaining clutch discs and plates.

4) On non "Powr-Lok" differentials only, remove peening and drift pinion shaft lock pin out of carrier. Remove gears, shaft and shims from carrier.

REASSEMBLY AND ADJUSTMENT

"POWR-LOK" CASE ASSEMBLY

Case Assembly - 1) On "Powr-Lok" differentials, install clutch plates and discs alternately into flange half of case. Install two belleville clutch plates so that convex sides are against case. Install side ring and position one side gear into ring recess. Install cross shafts. Install pinion cross shafts complete with pinion gears ensuring that ramps on shafts coincide with mating ramps in case.

2) Assemble differential case halves ensuring that reference marks are lined up and clutch friction plate tongues are aligned with grooves in differential case. Install bolts but do not tighten yet. Check alignment of splines by inserting both stub axles. Tighten differential case bolts with stub axles in position. With one stub axle locked,  other axle must not turn more than .75" (.19 mm) measured on a 6" (152 mm) radius.

3) On non "Powr-Lok" differentials, install pinion shaft, shims and gears into differential carrier. Secure lock pin by peening.

MEASURING SIDE BEARING PRELOAD

Side Bearing Preload - Install differential side bearings, without shims, on differential case, making sure that bearings and housing are perfectly clean. Place differential assembly in housing. Install dial indicator with indicator leg against back face of ring gear. Using suitable pry bars between housing and bearing cups, move differential assembly fully to one side of housing. Zero dial indicator and move assembly ot other side. Record indicator reading and add .009" (.20 mm) to reading to give total shim pack required. Remove differential assembly from housing.

Drive Pinion Depth - 1) Place pinion, together with inner bearing cone, into housing. Turn housing over and support pinion. Install pinion outer bearing cone, flange, washer and nut, omitting collapsible spacer, oil slinger and oil seal, tighten nut. Using suitable dial indicator support fixture (SL3) zero dial indicator on setting block (4.H.A.). Place dial indicator fixture firmly on face of pinion and note dial indicator reading to bottom of housing bearing bore (see illustration).

2) The indicator reading shows deviation of pinion setting from zero cone setting. This value should agree with value etched on face of pinion at bottom. For example, if value etched on pinion is -2, dial indicator should read - .002". If setting is incorrect, dismantle pinion and remove pinion inner bearing cup. Add or remove shims as required, reassemble and recheck pinion depth.

3) When setting is correct, extract pinion from housing sufficiently far to remove outer bearing cone. Install collapsible spacer to pinion ensuring that it seats firmly on machined shoulder of pinion. Insert pinion into housing, install outer bearing cone, oil slinger and oil seal. Lightly grease splines of pinion shaft and install flange. Install new washer on end of pinion with convex side facing end of shaft. Install but DO NOT tighten nut.

MEASURING PINION DEPTH

Backlash Adjustment - 1) Place differential assembly, complete with side bearings but less shims, in housing. Ensure that bearings and housing are perfectly clean. Install dial indicator on housing with feeler on back face of ring gear. Pry differential case and ring gear assembly away from pinion until opposite side bearing is seated against housing. Zero dial indicator at this point.

2) Move differential assembly towards pinion until ring gear is deeply meshed with pinion. Note indicator reading and from this value, subtract the backlash allowance etched on drive gear (eg. B/L.007 denotes .007"). This result will yield the thickness of shims (in inches) to be placed between differential case and side bearing on ring gear side of differential. Install this thickness of shims, taking shims from pack determined previously under "Side Bearing Preload". Install balance of total shims required on opposite side of case. An example of calculations required as follows

EXAMPLE

     Side Bearing Preload Reading...........................   .080"

     PLUS Preload Value........................................   .009"

     Total Shim Pack.............................................   .089"

     Pinion-to-Ring Gear Clearance..........................  .042"

     MINUS Etched Backlash Value.........................  .007"

     Total Ring Gear Side Shims..............................  .035"

     Total Shim Pack..............................................  .089"

     MINUS Ring Gear Side Shims..........................  .035"

     Opposite Ring Gear Shim Pack.........................  .050"

MEASURING RING GEAR SIDE SHIM
THICKNESS

3) With shims calculated installed, lower differential assembly into position, lightly tapping bearing home with soft hammer. Make sure ring and pinion gears mesh as installation proceeds. Install side bearing cap bolts. Mount dial indicator on housing with feeler against back face of ring gear. Turn pinion by hand and check ring gear run out. If run out exceeds specifications, disassemble differential, clean all mounting surface and check for burrs.

4) Now place dial indicator to measure ring gear backlash. Move ring gear and check that backlash is to specification etched on ring gear. If backlash is not to specifications, transfer necessary shims from side of differential case to the other NOTE - To increase backlash, remove shims from ring gear side and install on opposite side and visa versa. Finally, run a gear tooth contact pattern and adjust shims as necessary.

Pinion Bearing Preload - Install pinion and stub axle oil seals. Install stub axles following procedure give under stub axle removal and installation. Tighten flange to ensure correct seating of taper roller bearings. Use care not to overtighten nut. If not is overtighten, install a new collapsible spacer as pinion bearing preload will otherwise be incorrect. Install final drive rear cover using new gasket and suitable sealer (Hylomar).

MEASURING RING GEAR BACKLASH

1974 Jaguar Wheel Alignment Guide

JAGUAR SPECIFICATIONS AND ADJUSTMENTS

TIRE INFLATION (COLD)
Before attempting to check or adjust wheel alignment, make sure tires are properly inflated. Refer to owner's manual for manufacturer's specifications.

RIDING HEIGHT
XJ6 & XJ12 (Front) - Check that vehicle is full of gasoline oil and water, and that tires are properly inflated. Press down on front bumper and slowly release, then lift up on bumper and slowly release, this will settle front suspension. Measure distance between center of headlight and ground on both sides of vehicle. Correct height should be 24.6" (611 mm) minimum. To adjust, install or remove spring spacers from front coil spring. NOTE - Spring spacers are 1/8" (3.2 mm) thick, and will change riding height approximately 5/16" (7.9 mm).
XKE V-12 (Front) - Check that vehicle is full of gasoline, oil, and water and that tires are properly inflated. Roll vehicle forward three car lengths to settle suspension system. Measure distance from lower front sub-frame to ground on each side of vehicle. This measurement should be 6 1/4±1/4". If necessary to adjust, loosen lock nut on cam adjuster of lower control arm. Rotate cam adjuster to give correct height. Tighten locknut and recheck riding height.
All Models (Rear) - Check that vehicle is full of gasoline water and oil, and that tires are properly inflated. Roll forward three car lengths to settle suspension system. Measure distance between lower surface of rear crossmember and ground on both sides of vehicle. Correct height should be 7.45±.25" (189±6mm) on XJ6 and XJ12 models or 7.9±.25" (201±6 mm) on XKE V-12. If height is incorrect, it will be necessary to replace all four rear springs.

Caster and Camber Setting Tool (XJ6 & XJ12)

PREPARATION FOR CASTER AND CAMBER ADJUSTMENT (XJ6 & XJ12)
Ensure vehicle is on level ground and that tires are properly inflated. Before checking or adjusting caster or camber it will be necessary to fabricate two setting tools (see illustrations). Compress front suspension and insert tools under upper control arms adjacent to control arm rubber stops and over brackets welded to bottom of control arms. Compress rear suspension and install suitable suspension setting links (J.25), to lock rear suspension in place (see illustration). Vehicle is now locked in half-loaded condition and caster and camber can be checked and adjusted.

LOCKING REAR SUSPENSION (All Models)

CASTER
NOTE - Before adjusting caster angle, make sure car is standing at normal riding height.

XJ6 and XJ12 - If caster angle is not within specifications, adjust by moving shims on front and rear of upper control arm ball joint. To increase caster, loosen bolts securing upper ball joint and move shims from rear of ball joint to front of ball joint. To decrease caster, reverse procedure. Tighten ball joint attaching bolts and recheck caster angle
XKE V-12 - Before attempting to check or adjust caster angle, it will be necessary to simulate a half-loaded condition. This is accomplished by use of wooden blocks 6.25" high placed under caster of front sub-frame lower crossmember.. Load vehicle until crossmember contact wooden block. If caste ris not to specifications, adjust by rotating threaded shaft of upper control arm. With lock nuts loose and control arm bushing brackets loosened on sub-frame, rotate threaded shaft clockwise to decrease caster or counterclockwise to increae caster. Tighten shaft lock nuts and bolts on control arm bushing brackets.

CAMBER
NOTE - Before attempting to check or adjust camber angle it will be necessary to make sure that vehicle is standing at normal riding height.

XJ6 & XJ12 (Front) - With wheels in straight-ahead position, measure camber angle. NOTE - Two front wheels must be within 1/4 degrees of each other. Adjustment is accomplished by means of shims placed between control arm mounting bracket and the frame. Adding shims decreases camber angle. NOTE - Be sure to use the same number of shims on each bolt otherwise castor angle will be affected.
XKE V-12 (Front) - Before attempting to check or adjust camber angle, it will be necessary to simulate a half-loaded condition. This is accomplished by use of wooden blocks 6.25" high. Place wooden blocks under center of front sub-frame and load vehicle until sub-frame touches wooden blocks. If camber is not to specifications, adjust be adding or subtracting shims between upper control arm shaft and sub-frame. Shims are available in several thicknesses. The addition of one 1/16" shim will change camber angle 1/4 degrees.
All Models (Rear) - Before checking rear wheel camber, rear suspension must be in the half-loaded position. See Preparation for Caster and Camber Adjustment. To adjust, remove suspension setting links (JD.25), raise and support rear of vehicle and remove wheels. Loosen nuts securing half-shaft to brake disc, then add or remove shims as required to bring camber angle within specifications. NOTE - Addition of one .020" (5 mm) shim will alter camber 1/4 Degrees. Retighten nuts and bolts and check camber angle.

TOE-IN
All Models - Place wheels in straight ahead position and measure toe-in. If not to specifications, adjust by loosening steering link lock nuts and rotating adjuster sleeves to obtaining correct toe-in. Tighten lock nuts and recheck toe-in.