ALL MODELS (1971-74)
DESCRIPTIONAn integral type housing, hypoid design, with centerline of pinion set below centerline of ring gear. Semi-floating axle shafts are retained in housing by ball bearings and a bearing retainer at axle housing outer ends. All-adjustments are pre-formed using selective fit shims and gaskets.
REMOVAL AND INSTALLATION
AXLE SHAFT AND BEARINGS
1) Remove brake drum retainers and remove brake drum. Remove bolts securing bearing retainer plate to axle housing. These bolts are accessible through holes in axle shaft flange. Pull axle shaft and bearing assembly out of axle housing.
2) Loosen inner retainer ring by nicking it deeply with a cold chisel in several places. It will then slide off easily. press bearing and seal assembly from axle shaft using arbor press and suitable tool to hold and support bearing.
3) To install, inspect housing and axle shaft and lightly coat wheel bearing bore with axle lubricant. Place bearing retainer plate on axle shaft, and press new wheel bearing on shaft using suitable tool. NOTE - Do not attempt to press on both bearing and inner retainer at the same time.
4) Using suitable bearing installation tool, press bearing inner retainer ring on shaft until retainer seats firmly against bearing. Insert axle shaft in housing and engage splines. Top shaft into position. Install bolts securing bearing retainer plate and install brake and drum retainers.
REAR AXLE ASSEMBLY
1) Raise vehicle and remove wheels. Mark propeller shaft for proper alignment and disconnect from drive pinion flange. Release parking brake; then rmeove locknut and adjusting nut from handbrake cable and disconnect cable from relay lever. Disconnect brake line from brake hose.
2) Raise and support center of rear axle and disconnect shock absorbers from axle. Remove rear axle support. Remove two stabilizer bar retaining clamps from rear axle housing. Remove rear spring "U" bolt nuts and detach bolts and plates. Lift axle assembly and remove from vehicle.
3) To install, lift rear axle assembly into position on spring, being sure that it is correctly located over spring pilot bolts. Align and loosely fit propeller shaft to drive pinion flange. Fit "U" bolts over axle, slide on lower plates, install new locknuts and tighten.
4) Using a suitable tool, hold rear stabilizer bar onto mounting pads on axle housing and install retaining clamps. Insert retaining clamp bolts, check for binding, and tighten. Raise center of rear axle and install shock absorbers. Remove axle support.
4) Using a suitable tool, hold rear stabilizer bar onto mounting pads on axle housing and install retaining clamps. Insert retaining clamp bolts, check for binding, and tighten. Raise center of rear axle and install shock absorbers. Remove axle support.
5) Reconnect brake line to brake hose and handbrake cable to relay lever on rear axle housing. Adjust nut until relay lever is just clear of stop, tighten locknut. Tighten driveshaft to pinion flange bolts and bleed rear brake system. Fill rear axle housing with lubricant, mount rear wheels and lower vehicle.
OVERHAUL
DIFFERENTIAL CASE
Disassembly - 1) Raise vehicle and remove wheels and axle shaft assemblies. Mark propeller shaft for correct realignment and disconnect from pinion flange. Remove ten cover attaching bolts, cover and gasket and drain rear axle oil. Discard gasket and thoroughly clean cover.
2) Remove differential bearing caps and mark caps for correct repositioning. Lift differential out of axle housing using two pry bars. Remove tapered roller bearing from each side of differential assembly using a suitable puller. Remove adjusting shims from differential housing. Remove ring gear attaching bolts and ring gear from differential assembly.
3) Using a suitable drift, remove locking pin securing differential pinion shaft in differential case and remove differential pinions, side gears and adjusting shims. Hold drive pinion flange and remove pinion nut, retain nut for use during assembly operations. Remove pinion flange using a suitable puller, then remove pinion from axle housing. Remove bearing spacer from pinion. Remove large roller bearing from pinion shaft using press and suitable fixtures. Remove small tapered shaft using press and suitable fixtures. Remove small tapered roller bearing and seal from axle housing using a suitable drive. Drive bearing races out from axle housing with a drift.
CHECKING PINION DEPTH |
2) Install dummy pinion (part of special tool) into axle housing with pinion bearing but no shims. Lightly lubricate bearings and tighten tool until correct pinion bearing pre-load is obtained. Rotate dummy pinion several times to unsure seating of bearings. It is essential that the torque reading be recorded and followed for further adjustment of drive pinion. This torque must also be check after installation of drive pinion with selected spacer.
3) Mount dial indicator on mounting bracket and set to zero on dummy pinion. Slowly rotate dial indicator over cross bar of tool and read total deflection of pointer. This reading gives the exact thickness of the shims to be used. When pinion is marked "-1" or "-2" this amount must be added to indicator reading. When gear is marked "+1" or "+2" this amount must be subtracted from reading to obtain correct shim thickness. Using a micrometer, select a shim of the determined thickness.
MEASURING SIDE GEAR CLEARANCE |
5) Position ring gear on differential case and locate with bolts. Pull ring gear evenly into position with bolts. Remove old bolts and install new bolts and tighten. To determine total play of differential case in axle housing: Press tapered roller bearing onto differential case without shims after first inspecting bearings for damage. Install pressure blocks (part of tool 170P-4136) into axle housing on each side of differential case and install bearing caps (number to number) and tighten attaching bolts. Now, loosen and tighten finger tight.
6) Tighten pressure spindle (tool T70P-4136) to a torque of 43 INCH lbs. Rotate differential several times and recheck torque. Mount dial indicator on rear axle housing so that feeler attach inner side of ring gear flange and zero indicator. Place pressure spindle into other side of housing and tighten to 43 INCH lbs. Read and note amount of indicator delfection and record as total play of differential case is rear axle housing. Loosen pressure spindle, tilt dial indicator to side and remove differential, pressure spindle and pressure blocks.
7) To determine thickness of pinion bearing spacer: Slide master spacer (tool T70P-4137) onto pinion. Using soft wire solder of about .08" (2 mm) diameter, form a ring which matches drive pinion shaft diameter and place it onto gauge ring. Position pinion into rear axle housing and slid on small taper roller bearing and pinion flange. Install old self-locking nut, hold drive pinion flange and slowly tighten nut to its specifications using care not to exceed torque value or procedure must be respected with new solder wire. Carefully remove compressed solder wire and measure thickness at two opposite points. If thickness varies, average the two values.
DIFFERENTIAL SETUP & BLOCKS INSTALLATION |
9) To determine differntial case bearing shim thickness. Place pressure blocks back into axle housing and place differential case with bearing races into axle housing. Install bearing caps, tighten screw, then loosen and tighten finger tight. Using pressure spindle, press differential housing with a torque of 43 INCH lbs. away from drive pinion. Rotate pinion several times. Position feeler of dial indicator gauge at right angle to one tooth of ring gear. Measure tooth flank backlash at 4 points, each time turning gear two bolt heads further. Deviations of tooth flank backlash must not exceed .002" (.05 mm). Insert pressure spindle into other side of axle housing and screw in slowly until there is the specified value of tooth flank backlahs.
10) Position dial indicator so that feeler contact ring gear flange and zero indicator. Insert spindle into the other side of axle housing and torque to 43 INCH lbs. Read and record indicated deflection on indicator as ring gear back side shim thickness. Remove pressure spindle, differential case and pressure blocks from axle housing.
MEASURING RING GEAR BACKLASH |
12) Remove differentail case bearings and position required shims on differential case. Using suitable tools, press tapered roller bearing onto differential case after checking bearing for damage. Insert differential case in axle housing and position bearing caps as previously marked. Coat bolt threads with sealing compound and insert bolts.
13) Position dial indicator feeler in a vertical position on one ring gear tooth and check that pinion to ring gear backlash is to specifications. If not, differential must be removed and shims adjusted. If backlash is too greast, remove shims from ring gear face side and transfer to ring gear back side and vise versa. Do NOT increase or decrease number of shims, but only interchange between one side and the other.
14) Finally check gear contact pattern and adjust as necessary to obtain correct patter. Position housing cover and gasket on axle housing and install and tighten bolts. Attach parking brake operating lever to rear axle housing and connect return spring to bracket on housing. Install rear brake assemblies on axle housing and connect parking brake cable to brake assemblies.