Part 2
ADJUSTMENTFor quiet and reliable final drive operation, the following five adjustments must be made correctly:
1. Side bearing preload
2. Pinion gear height
3. Side bearing preload
4. Ring gear-to-pinion backlash. Refer to image.
5. Ring and pinion gear tooth contact pattern.
PINION GEAR HEIGHT
1. Make sure all parts are clean and that the bearings are well lubricated.
2. Assemble the pinion gear bearings into the pinion pre-load shim selector tool, J34309.
- Rear Pinion Bearing - the rear pinion bearing pilot, J34309-8, is used to center the rear pinion bearing only. The rear pinion bearing locking seat, J34309-4, is used to lock the bearing to the assembly.
- Front Pinion Bearing - make sure the J34309-3, front pinion bearing seat is secured tightly against the J34309-2 gauge anvil. Then turn the front pinion bearing pilot, J34309-5, to secure the bearing in its proper position.
3. Place the pinion preload shim selector tool gauge screw assembly, J34309-1, with the pinion rear bearing inner cone installed, into the final drive housing.
4. Install the J34309-2 gauge anvil with the front pinion bearing into the final drive housing and assemble it to the J34309-1 gauge screw. Make sure that the J34309-16 gauge plate will turn a full 360 degrees, and tighten the two sections by hand to set bearing pre-load.
5. Turn the assembly several times to seat the bearings.
6. Measure the turning torque at the end of the J34309-2 gauge anvil using torque wrench J25765A.
Turning torque specification: 0.4 - 0.9 Nm (4 - 9 kg.cm, 3.5 - 7.8 inch lbs.)
7. Place the J34309-12 "H23313" pinion height adapter onto the gauge plate and tighten it by hand.
CAUTION: Make sure all machined surfaces are clean.
PINION HEIGHT ADJUSTING WASHER SELECTION
8. Position the J25269-18 side bearing discs and the arbor into the side bearing bores.
9. Install the bearing caps and torque the bolts.
Specification: 93 - 103 Nm (9.5 - 10.5 kg.m, 69 - 76 ft. lbs.)
10. Select the correct standard pinion height adjusting washer thickness using a standard gauge of 2.5, 3.0, or 3.5 mm (0.098, 0.118, or 0.138 inch) and your J34309-1 01 feeler gauge. Measure the distance between the J34309-12 "H23313" pinion height adapter and the arbor.
11. Write down your exact total measurement.
12. Correct the pinion height washer size by referring to the "pinion head height number".
There are two numbers painted on the pinion gear. The first one refers to the pinion and ring gear as a matched set and should be the same as the number on the ring gear. The second number is the "pinion head height number", and it refers to the ideal pinion height from standard for the quietest operation. Use the following chart to determine the correct pinion height washer. Refer to image.
13. Remove the J34309 pinion preload shim selector tool from the final drive housing and disassemble to retrieve the pinion bearings.
TOOTH CONTACT
Gear tooth contact pattern check is necessary to verify correct relationship between ring gear and drive pinion. Hypoid gear sets which are not positioned properly in relation to one another may be noisy, or have short life or both. With a pattern check, the most desirable contact for low noise level and long life can be assured.
1. Thoroughly clean ring gear and drive pinion teeth.
2. Sparingly apply a mixture of powdered ferric oxide and oil or equivalent to 3 or 4 teeth of ring gear drive side.
3. Hold companion flange steady by hand and rotate the ring gear in both directions.
ASSEMBLY
DIFFERENTIAL CASE
1. Install side gears, pinion mate gears and thrust washers into differential case.
2. Fit pinion mate shaft to differential case so that it meets lock pin holes.
3. Adjust backlash between side gear and pinion mate gear by selecting side gear thrust washer. Refer to image.
Backlash between side gear and pinion mate gear (Clearance between side gear thrust washer and differential case): 0.10 - 0.20 mm (0.0039 - 0.0079 inch)
4. Install pinion mate shaft lock pin with a punch.
Make sure lock pin is flush with case.
5. Apply gear oil to gear tooth surfaces and thrust surfaces and check to see they turn properly.
6. Install differential case assembly on ring gear.
Tighten bolts in a criss-cross pattern, lightly tapping bolt head with a hammer.
7. Press-fit side bearing inner cones on differential case with Tool.
Tool number:
A ST33190000 (J25523)
B ST33081000 ( - )
DIFFERENTIAL CARRIER
1. Press-fit front and rear bearing outer races with Tools.
Tool number:
A ST30611000 (J25742-1)
B ST30621000 (J25742-5)
C ST30613000 (J25742-3)
2. Select drive pinion height adjusting washer.
3. Install drive pinion adjusting washer in drive pinion, and press-fit pinion rear bearing inner cone in it, with press and Tool.
Tool number: ST30901000 (J26010-01)
4. Place pinion front bearing inner cone in gear carrier.
5. Apply multi-purpose grease to cavity at sealing lips of oil seal. Install front oil seal.
Tool number:
A ST30720000 (J25405)
B KV38102510 ( - )
6. Install drive pinion bearing spacer, pinion bearing adjusting shim and drive pinion in gear carrier.
7. Insert companion flange into drive pinion by tapping the companion flange with a soft hammer.
8. Tighten pinion nut to the specified torque.
The threaded portion of drive pinion and pinion nut should be free from oil or grease.
Tool number: KV38104700 (J34311)
9. Turn drive pinion in both directions several times, and measure pinion bearing preload.
Tool number: ST3127SO00 (J25766-A)
Pinion bearing preload (Without front oil seal): 1.4 - 1.7 Nm (14 - 17 kg.cm, 12 - 15 inch lbs.)
If preload is out of specification, adjust the thickness of spacer and shim combination by replacing shim and spacer with thinner one.
- Start from the combination of thickest spacer and shim.
- Combine each spacer and shim thickness one by one until the correct specification are achieved.
Drive pinion bearing preload adjusting spacer and shim: Refer to image.
10. Install differential case assembly with side bearing outer races into gear carrier.
11. Position side bearing adjusters on gear carrier with threads properly engaged; screw in adjusters lightly at this stage of assembly.
Tool number: ST32580000 (J34312)
12. Align mark on bearing cap with that on gear carrier and install bearing cap on gear carrier.
- Do not tighten at this point to allow further tightening of side bearing adjusters.
13. Tighten both right and left side bearing adjusters alternately and measure ring gear backlash and total preload at the same time. Adjust right and left side bearing adjusters by tightening them alternately so that proper ring gear backlash and total preload can be obtained.
Ring gear-to-drive pinion backlash: 0.13 - 0.18 mm (0.0051 - 0.0071 inch)
- When checking preload, turn drive pinion in both directions several times to set bearing rollers.
Tool number: ST3127SO00 (J25765-A)
Total preload: 1.7 - 2.5 Nm (17 - 25 kg.cm, 15 - 22 inch lbs.)
14. Tighten side bearing cap bolts.
15. Install side lock finger in place to prevent rotation during operation.
16. Check runout of ring gear with a dial indicator.
Runout limit: 0.08 mm (0.0031 inch)
- If backlash varies excessively in different places, the variance may have resulted from foreign matter caught between the ring gear and the differential case.
- If the backlash varies greatly when the runout of the ring gear is within a specified range, the hypoid gear set or differential case should be replaced.
17. Check tooth contact.