Rear Axle - C213R

PINION DEPTH-BEARING PRELOAD-GEAR BACKLASH





Ring gear and pinion are supplied as matched sets. Identifying numbers for the ring gear and pinion are painted onto the pinion gear shaft and the side of the ring gear. A plus (+) number, minus (-) number or zero (0) along with the gear set sequence number (2) (01 to 99) is on each gear. This first number (1) the amount (in thousandths of an inch) the depth varies from the standard depth setting of a pinion marked with a (0). The next two numbers are the sequence number of the gear set. The standard depth provides the best teeth contact pattern.





Compensation for pinion depth variance is achieved with select shims (4). The shims are placed behind the rear pinion bearing.
If installing a new gear, note the depth variance number of the original and replacement pinion. Add or subtract this number from the original depth shim/oil slinger to compensate for the difference in the depth variances. The numbers represent thousands of an inch deviation from the standard. If the number is negative, add that value to the required thickness of the depth shims. If the number is positive, subtract that value from the thickness of the depth shim.

Pinion Gear Depth Variance Chart: Note where Old and New Pinion Marking columns intersect. Intersecting figure represents plus or minus the amount needed.

PINION GEAR DEPTH VARIANCE:

PINION DEPTH MEASUREMENT





Measurements are taken with pinion bearing cups and pinion bearings installed in the housing. Take measurements with Pinion Gauge Set and Dial Indicator C-3339 (1).





1. Assemble Pinion Height Block 6739 (2), Pinion Block 8540 (1) and rear pinion bearing onto Screw 6741.
2. Insert assembled height gauge components, rear bearing and screw into housing through pinion bearing cups.





3. Install front pinion bearing and Cone-Nut 6740 on the screw. Tighten Cone-Nut until Torque To Rotate screw is 3.4 Nm (30 inch lbs.).
4. Place Arbor Disc 8541A (1) on Arbor D-115-3 (3) and position in the housing side bearing cradles. Install differential bearing caps on arbor discs and tighten cap bolts to 41 Nm (30 ft. lbs.).





5. Assemble Dial Indicator C-3339 (3) into Scooter Block D-115-2 (2) and secure set screw.
6. Place Scooter Block with Dial Indicator on the pinion height block, so dial probe and scooter block is flush against the pinion height block. Hold scooter block in place and zero the dial indicator. Tighten dial indicator face lock screw.
7. Slide the dial indicator probe over the edge of the pinion height block and on to the arbor bar (1). With the scooter block against the pinion height block.
8. When dial probe contacts the arbor bar, the dial pointer will turn clockwise. Continue moving the dial indicator to the crest of the arbor bar and record the highest reading.
9. Select a shim equal to the dial indicator reading, plus the drive pinion gear depth variance number marked on the shaft of the pinion. For example, if the depth variance is -2, add +0.002 in. to the dial indicator reading. Then subtract 0.04064 mm (0.0016 inch) from the total measurement. This will be the correct shim selection for the pinion height.

DIFFERENTIAL BEARING PRELOAD AND GEAR BACKLASH





The following must be considered when adjusting bearing preload and gear backlash:
- The maximum ring gear backlash variation is 0.076 mm (0.003 inch).
- Mark the gears so the same teeth are meshed during all backlash measurements.
- Maintain the torque while adjusting the bearing preload and ring gear backlash.
- Excessive adjuster torque will introduce a high bearing load and cause premature bearing failure. Insufficient adjuster torque can result in excessive differential case free-play and ring gear noise.
- Insufficient adjuster torque will not support the ring gear correctly and can cause excessive differential case free-play and ring gear noise.

NOTE: The differential bearing cups will not always immediately follow the threaded adjusters as they are moved during adjustment. To ensure accurate bearing cup responses to the adjustments:

- Maintain the gear teeth engaged (meshed) as marked.
- The bearings must be seated by rapidly rotating the pinion gear a half turn back and forth.
- Do this five to ten times each time the threaded adjusters are adjusted.

1. Use Wrench C-4164 to adjust each threaded adjuster inward until the differential bearing free-play is eliminated. Allow some ring gear backlash approximately 0.25 mm (0.01 inch) between the ring and pinion gear. Seat the bearing cups with the procedure described above.
2. Install dial indicator (1) and position the plunger against the drive side of a ring gear tooth (2). Measure the backlash at 4 positions (90 degrees apart) around the ring gear. Locate and mark the area of minimum backlash.
3. Rotate the ring gear to the position of the least backlash. Mark the gear so that all future backlash measurements will be taken with the same gear teeth meshed.





4. Loosen the right-side, tighten the left-side threaded adjuster with Adjuster Wrench C-4164 (3). Obtain backlash of 0.076 - 0.102 mm (0.003 - 0.004 inch) with each adjuster tightened to 14 Nm (10 ft. lbs.). Seat the bearing cups with the procedure described above.
5. Tighten the differential bearing cap bolts to 136 Nm (100 ft. lbs.).
6. Tighten the right-side threaded adjuster to 102 Nm (75 ft. lbs.). Seat the bearing cups with the procedure described above. Continue to tighten the rightside adjuster and seat bearing cups until the torque remains constant at 102 Nm (75 ft. lbs.)
7. Measure the ring gear backlash. The range of backlash is 0.12 - 0.20 mm (0.005 - 0.008 inch).
8. Continue increasing the torque at the right-side threaded adjuster until the specified backlash is obtained.

NOTE: The left-side threaded adjuster torque should have approximately 102 Nm (75 ft. lbs.). If the torque is considerably less, the complete adjustment procedure must be repeated.

9. Tighten the left-side threaded adjuster until 102 Nm (75 ft. lbs.) torque is indicated. Seat the bearing rollers with the procedure described above. Do this until the torque remains constant.
10. Install the threaded adjuster locks and tighten the lock screws to 11 Nm (8 ft. lbs.).
11. After the proper backlash is achieved, perform the Gear Contact procedure.

GEAR CONTACT PATTERN





1. Wipe clean each tooth of the ring gear.
2. Apply gear marking compound to all of the ring gear teeth.
3. Verify bearing cap bolts are torque to 136 Nm (100 ft. lbs.).
4. Apply parking brakes lightly to create at 14 Nm (10 ft. lbs.) pinion rotating torque.
5. Rotate the pinion/pinion yoke 4 full revolutions in each directions.
6. Read gear tooth contact pattern.
Gear contact pattern is correct. Backlash and pinion depth is correct.





Ring gear is too far away from the pinion gear, coast side toe (1) drive side heel (2). Decrease backlash by moving ring closer to the pinion gear using the adjusters.





Ring gear is too close to the pinion gear, drive side toe (1) coast side heel (2). Increase backlash by moving ring away from the pinion gear using the adjusters.





Ring gear is too far away from the pinion gear, drive side heel (1) coast side heel (2). Decrease backlash by moving ring gear closer to the pinion gear using the adjusters.





Ring gear is too close to the pinion gear, drive side toe (1) coast side toe (2). Increase backlash by moving ring gear away from the pinion gear using the adjusters.





Pinion gear is set too low. Increase pinion gear height, by increasing pinion depth shim thickness.





Pinion gear is set too high. Decrease pinion height by decreasing the pinion depth shim thickness.