BMW INTEGRAL CARRIER 2002 SERIES
DESCRIPTION
Differential has hypoid ring and drive pinion gear set and may have a clutch pack type limited slip unit. Differential housing has removable rear cover. Differential carrier is retained in the sides of the housing by retaining plates, and is supported by roller bearings. Drive pinion gear is supported by roller bearings, and in addition, a long neck housing has ball bearing supporting the drive pinion at the companion flange. Drive pinion preload is maintained by a collapsible spacer in the short neck housing, and by a spacer and shims in the long neck housing.
AXLE RATIO AND IDENTIFICATION
The ring and pinion gear set with Klingelnberg tooth design, can be identified by the letter "K" stamped on the head of the drive pinion gear; Gleason teeth are noted by on "H" or "F" stamping. To determine axle ratio, divide number of ring gear teeth by number of drive pinion gear teeth. The number of teeth on ring and drive pinion gears is stamped on forward left side of differential housing.
REMOVAL AND INSTALLATION
Drive Shafts and Universal Joints
Remove drive shaft after removing retaining bolts form axle and half shaft flanges. For universal joint or dust boot replacement, use the appropriate procedure below.
Constant Velocity Joint - Remove cover from joint housing, then remove snap ring from end of drive shaft. Remove clamps from boot then press drive shaft from joint. Remove dust boot. To install, reverse removal procedure using sealer on boot-to-joint surfaces and install seal cover after pakcing joint with suitable grease.
Sliding U-Joint - Drain oil form joint, note position of hose clamps, then remove clamps. Pull of housing and roller caps and coat needle bearings with grease. Remove dust boot from spacer ring and then remove boot and ring. To install, reverse removal procedure, locating hose clamps in original position.
Cross and Roller U-Joint - NOTE - If yoke is bent or twisted, complete drive shaft must be replaced. Remove bearing cup snap rings, then press out bearing cups using suitable arbor press or vise and supporting tools. Remove cross assembly from yoke. To install, hold cross between ears of drive shaft and partially install two bearing cups. Align cross with cups, then using arbor press or vise, press cups into yoke until snap rings can be inserted.
AXLE SHAFT AND BEARINGS
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| FIG. 2 SECTIONAL VIEW OF AXLE SHAFT ASSEMBLY |
Raise and support vehicle. Remove wheel, loosen castellated nut, securing flange to axle shaft, then using a suitable puller, remove flange. Remove dive shaft, then using a soft headed mallet, drive axle shaft inward and out of housing. Drive out bearings and seals, then remove spacer sleeve and shim . To install, reverse removal procedure noting the following: Install inner bearing, then determine distance between outer races of inner and outer bearings. Measure spacer and shim, then install spacer and a suitable shim that will obtain a wheel bearing play of .002-.004" (.05-10 mm). Pack bearings and hub with suitable grease, then using new seals, complete installation procedure.
DRIVE PINION COMPANION FLANGE OIL SEAL
NOTE - On short neck differential housing, complete disassembly of differential is required for seal replacement. Refer to Drive Pinion Gear Removal and Installation procedures for seal replacement.
Long Neck Differential Housing - Remove propeller shaft, nut retaining companion flange on drive pinion gear, companion flange and oil seal. To install, reverse removal procedure insuring seal installed depth is .24" (6 mm) from front of seal to front edge of housing.
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| FIG. 3 REMOVING AXLE DRIVE FLANGE |
AXLE FLANGE AND OIL SEAL
Removal - Remove drive shaft. Hold axle flange using suitable tools (604 wrench; 6040 Spacer) then remove flange retaining bolt. Using a suitable puller (20/10) and support bracket (7011-1) remove axle flange. Remove oil seal.
Installation - Fill between sealing lips of seal with grease, then install seal in retaining plate to a depth of .16" (4 mm). Thoroughly clean flange and carrier splines and if any backlash between splines exists apply small amount of locking compound to flange splines. Install flange and retaining bolt.
DIFFERENTIAL ASSEMBLY
Remove propeller shaft and drive shafts, tie drive shafts up out of way. Support differential and remove four frame-to-housing attaching bolts, two differential cover-to-bracket nuts, and two bracket-to-frame bolts. Remove differential assembly. To install, reverse removal procedure, insuring rear bracket is stress free when installed.
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| FIG. 4 CHECKING RING GEAR BACKLASH |
OVERHAUL
Disassembly
Differential Housing - Remove differential assembly as prevously outlined, and mount assembly in suitable holding fixture. Drain oil and mark drive pinion shaft and companion flange fro reassembly reference. Remove rear cover plate. Remove both axle flanges, as previously described, keeping right and left side ports separated. Mount a dial indicator to housing, and check ring gear runout for reference at time of reassembly. Make a gear tooth pattern check. NOTE - Refer to Rear Axle Gear Tooth Patterns in this section. Mark and remove carrier bearing retainer plates and shims. Turn housing rear opening upward, move carrier to right side, tilt and remove carrier from housing. Proceed as follows for standard or limited slip differential carrier disassembly.
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| FIG. 5 VIEW OF ASSEMBLED LIMITED SLIP UNIT WITH CASE REMOVED |
Standard Differential Carrier - Remove carrier bearings using suitable puller (Rollex LM503349). Remove bolts securing ring gear to carrier, then remove ring gear. Drive out pinon shaft lock pin, remove pinion gears shaft and pinion gears. Remove side gears with shims and thrust washers.
Limited Slip Differential Carrier - Remove carrier bearings using suitable puller, (HM 89449). Remove bolts securing case cover to ring gear flange, insert case and lift case of clutch and gear assembly. Separate ring gear from flange. Remove clutch components lift off hub, remove side gear and one set of pinion gears. REpeat procedure for other half of case.
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| FIG. 8 SECTIONAL VIEW OF LONG NECK HOUSING PINION SHAFT FRONT BEARING ASSEMBLY |
Drive Pinion Gear - 1) Remove differential carrier as previously outlined, then using an inch pound torque wrench, check preload on drive pinion gear. Hold companion flange and remove retaiining nut. Press drive pinion from flange and housing, then remove bearings. NOTE - On long neck housing, firt remove flange nut, flange, cover and shim. Using a suitable tool (6046) remove drive pinion lock nut, then press gear out.
2) Remove drive pinion shaft oil seal then using suitable tools (5109 and 5120) press drive pinion outer bearing cones from housing. NOTE - On short neck housing, remove rear bearing cone first. On long neck housing, remove forward bearing come first.
REASSEMBLY AND ADJUSTMENT
Differential Assembly - Reverse disassembly procedure noting the following checks and adjustments.
Drive Pinion Bearing Preload - 1) If original ring and pinion gear set is being installed, install drive pinion gear using original shim and new collapsible spacer. If a new gear set is being installed determine correct size of shim to use in the following manner: Drive pinion gears may be stamped either "+1,2,3 etc", or "-1,2,3. etc". Compare marks on tapered ends of old and new gears. Subtract the two numbers. In relation to original shim, a plus remainder means a thinner shim is required; a minus remainder means a thicker shim is required.
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| FIG. 8 SECTIONAL VIEW OF LONG NECK HOUSING PINION SHAFT FRONT BEARING ASSEMBLY |
2) Remove then reinstall drive pinion, bearings and cones, as required, so new shim(s), collapsable spacer, and seal can be installed. NOTE - On long neck housing, preload must be etablished with pinion lock nut before installing front housing cover.
3) Install companion flange and nut (short neck housing), or pinion lock nut (long neck housing) and tighen nut to obtain specified preload NOTE - If preload is exceeded, new collpsable spacer must be installed, and procedure repeated.
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| FIG. 11 CHECKING SIDE GEAR-TO-PINION GEAR BACKLASH ON STANDARD DIFFERENTIAL |
Side-to-Pinion Gear Backlash (Standard Differential) - With pinion gears and one side gear installed, mount dial indicator to carrier. Force side gear against case, zero indicator then force side gear against pinion gears. With proper shim and thrust washer, backlash should be as specified and preload of all three gears should not exceed 14 ft. lbs. (1.9 mkg). Repeat procedure on opposite side gear, then retain both side gears pressed outward against carrier, so axle drive flange retaining can be later be installed.
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| FIG. 12 MEASURING LIMITED SLIP CLUTCH ASSEMBLY INSTALLED HEIGHT WITH PRESSURE APPLIED |
Clutch Assembly Endplay (Limited Slip Differential) - Assemble differential clutch and gear assembly, without ring gear or case. Apply 220 psi (15.5 kg/sq cm) to one end of assembly. Measure from inner surface of flange to top surface of spacer ring. Measure depth of case. If clutch assembly-to-housing end play is not to specification, adjust by using thicker or thinner inner clutch discs.
Checking Pinion Gear Torque (Limited Slip Differential) - With differential carrier is assembled, install axle flanges in carrier. Clamp one flange in vice and using an inch pound of torque wrench, turn other flange. If rotating torque of side and pinion gears is not to specifications, install thicker or thinner case cover to clutch assembly thrust washer.
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| FIG. 13 CHECKING PINION GEAR TORQUE ON LIMITED SLIP DIFFERENTIAL |
Differential Bearing Preload - With differential carrier installed in housing without ring gear, and with carrier bearing retainer plates installed without shims, thread a bolt in against differential pinion gear shaft. Equally tighten retainer plate bolts until specified bearing preload is obtained. Using feeler gauge, check clearance between retainer plate and housing to determine required shim thickness. Take required shims and install them equally under both retainer plates.
Ring-to-Drive Pinion Gear Backlash - After establishing differential bearing preload, check ring-to-pinion gear tooth contact pattern. While maintaining established shim thickness, move shims from one retainer plate to the other, as necessary, to obtain proper contact pattern. After setting backlash, complete differential reassembly procedure.
