Operation CHARM: Car repair manuals for everyone.

Part 1





REAR FINAL DRIVE


Disassembly and Assembly


COMPONENTS











ASSEMBLY INSPECTION AND ADJUSTMENT
- Drain the differential gear oil before inspection and adjustment. Changing Differential Gear Oil Checking Differential Gear Oil, "Changing Differential
Gear Oil".
- Remove and install the carrier cover as necessary for inspection and adjustment. C200, "Removal and Installation".

Total Preload Torque
1. Rotate drive pinion back and forth 2 to 3 times to check for unusual noise and rotation malfunction.
2. Rotate drive pinion at least 20 times to check for smooth operation of the bearing.





3. Measure total preload torque using Tool.






NOTE:
Total preload torque = Drive pinion bearing preload torque +
Side bearing preload torque
- If the measured value is out of the specification, check and adjust each part. Adjust the drive pinion bearing preload torque first, then adjust the side bearing preload torque.






Drive Gear Runout





1. Fit a dial indicator to the drive gear back face.
2. Rotate the drive gear to measure runout.






- If the runout is outside of the limit, check the condition of the drive gear assembly. Foreign material may be caught between the drive gear and differential case, or the differential case or drive gear may be deformed.
CAUTION:
Replace drive gear and drive pinion as a set.

Tooth Contact
Checking gear tooth contact pattern is necessary to verify correct relationship between drive gear and drive pinion. Gears which are not positioned in proper arrangement may be noisy and/or have a short life. Check gear tooth contact pattern to obtain the best contact for low noise and long life.





1. Apply red lead to drive gear.
NOTE:
Apply red lead to both faces of three to four gears, at four locations evenly spaced on the drive gear.





2. Rotate the drive gear back and forth several times. Then check for correct drive pinion to drive gear tooth contact as shown.
CAUTION:
Check tooth contact on drive side and reverse side.





3. If the tooth contact is improperly adjusted, follow the procedure below to adjust the pinion height (dimension X).





- If the tooth contact is near the face (face contact), or near the heel
(heel contact), use a thicker drive pinion height adjusting washers to move the drive pinion closer to the drive gear.
Inspection And Adjustment.





- If the tooth contact is near the flank (flank contact), or near the toe
(toe contact), use a thinner drive pinion height adjusting washers to move the drive pinion farther from the drive gear.
Inspection And Adjustment.

Backlash





1. Fit a dial indicator to the drive gear face to measure the backlash.






- If the backlash is outside of the specification, change the thickness of each side bearing adjusting washer.






CAUTION:
Do not change the total thickness of side bearing adjusting washers as it will change the side bearing preload torque.

Companion Flange Runout





1. Rotate companion flange and check for runout on the companion flange face (inner side of the bolt holes) and companion flange inner side (socket diameter) using suitable tool.






2. If the runout is outside the runout limit, follow the procedure below to adjust.
a. Rotate the companion flange on the drive pinion by 90�, 180� and 270� while checking for the position where the runout is minimum.
b. If the runout is still outside of the runout limit after the companion flange has been rotated on the drive pinion, possible cause could be an assembly malfunction of drive pinion and drive pinion bearing or a malfunctioning drive pinion bearing.
c. If the runout is still outside of the runout limit after repair of the assembly of drive pinion and drive pinion bearing or drive pinion bearing, replace the companion flange.

DISASSEMBLY

Differential Assembly
1. Remove carrier cover bolts.





2. Remove carrier cover using Tool.






CAUTION:
- Do not damage the mating surface.
- Do not insert flat-bladed screwdriver, this will damage the mating surface.





3. For proper reinstallation, paint matching marks on one side of side bearing cap.
CAUTION:
- Side bearing caps are line-board for initial assembly. The matching marks are used to reinstall them in their original positions.
- For matching mark, use paint. Do not damage side bearing cap.





4. Remove side bearing caps.





5. Remove differential case assembly using suitable tool.





- Keep side bearing outer races together with inner races. Do not mix them up. Also, keep side bearing adjusting washers together with bearings.





6. Remove side bearing inner race using Tools.






CAUTION:
- Engage puller jaws in groove to prevent damage.
- To prevent damage to the side bearing and drive gear, place copper plates between these parts and vise.
- It is not necessary to remove side bearing inner race except if it is replaced.





7. For proper reinstallation, paint matching mark on one differential case assembly.
CAUTION:
Use paint for matching marks. Do not damage differential case or drive gear.
8. Remove drive gear bolts.
9. Tap the drive gear off the differential case assembly using suitable tool.
CAUTION:
Tap evenly all around to keep drive gear from binding.





10. Remove the lock pin of pinion mate shaft from the drive gear side using suitable tool.





11. Remove pinion mate shaft.





12. Turn the pinion mate gear, then remove the pinion mate gear, pinion mate thrust washer, side gear and side gear thrust washer from differential case.

Drive Pinion Assembly
1. Remove differential case assembly. SEE Disassembly and Assembly.





2. Remove drive pinion lock nut using suitable tool.
3. Put matching marks on the companion flange and drive pinion using paint.
CAUTION:
Use paint to make the matching marks. Do not damage the companion flange or drive pinion.





4. Remove companion flange using suitable Tool.





5. Remove drive pinion assembly from gear carrier using suitable tool.
CAUTION:
Do not drop drive pinion assembly.
6. Remove front oil seal.
7. Remove drive pinion front bearing inner race.
8. Remove collapsible spacer.





9. Remove drive pinion rear bearing inner race and drive pinion height adjusting washer using Tool.










10. Tap drive pinion front and rear bearing outer races uniformly with a brass bar or equivalent to remove.
CAUTION:
Do not damage gear carrier.

INSPECTION AFTER DISASSEMBLY
Clean up the disassembled parts. Then, inspect if the parts are worn or damaged. If so, follow the measures below.

Drive Pinion and Drive Gear
- If the drive pinion and drive gear teeth do not mesh or line-up correctly, determine the cause and adjust, repair, or replace as necessary.
- If the drive pinion or drive gear are worn, cracked, damaged, pitted or chipped (by friction) noticeably, replace with new drive pinion and drive gear.
- Drive pinion and drive gear are supplied in matched sets only. Matching numbers on both drive pinion and drive gear are etched for verification. If a new drive pinion and drive gear set are being used, verify the numbers of each drive pinion and drive gear before proceeding with assembly.

Bearing
- If bearings are chipped (by friction), pitted, worn, rusted, scratched, or unusual noise is coming from bearing, replace with new bearing assembly (as a new set).
- Bearing must be replaced with a new one whenever disassembled.

Side Gear and Pinion Mate Gear
- If any cracks or damage are found on the surface of the teeth, replace with new one.
- If any worn or chipped marks are found on the side of the side gear and pinion mate gear which contact the thrust washer, replace with new one.
- Replace both side gear and pinion mate gear as a set when replacing side gear or pinion mate gear.

Side Gear Thrust Washer and Pinion Mate Thrust Washer
- If any chips (by friction), damage, or unusual wear are found, replace with new one.

Gear Carrier
- If any wear or cracks are found on the contact sides of gear carrier, replace with new one.

Companion Flange
- If any chips (about 0.1mm, 0.004 in) or other damage on the companion flange surface which contacts the front oil seal lips are found, replace with new one.

ADJUSTING AND SELECTING WASHERS

Side Gear Back Clearance
- Assemble the differential parts if they are disassembled. Refer to "Differential Assembly".





1. Place the differential case straight up so that the side gear to be measured is upward.





2. Using feeler gauges, measure the clearance between the side gear back and differential case at three different points, while rotating the side gear. Average the three readings to calculate the clearance. (Measure the clearance of the other side as well.)






- If the side gear back clearance is outside of the specification, use a thicker or thinner side gear thrust washer to adjust.
SEE Disassembly and Assembly.






CAUTION:
- Insert feeler gauges with the same thickness on both sides to prevent side gear from tilting.
- Each gear should rotate smoothly without excessive resistance during differential motion.
- Select a side gear thrust washer for right and left individually.
NOTE:
Side gear back clearance is clearance between side gear and differential case for adjusting side gear backlash.

Side Bearing Preload Torque
- A selection of side bearing adjusting washers is required for successful completion of this procedure.





1. Apply differential gear oil to the side bearings, and install the differential case assembly with the side bearing outer races into the gear carrier.
CAUTION:
Do not reuse side bearing outer race when replacing side bearing inner race (replace as a set).





2. Insert the left and right original side bearing adjusting washers in place between side bearings and gear carrier using Tool.










3. Align the matching mark on the side bearing cap with the matching mark on the gear carrier.
4. Install the side bearing caps and tighten the side bearing cap bolts to the specified torque. SEE Disassembly and Assembly, "Disassembly
and Assembly".
5. Turn the differential assembly several times to seat the side bearings.





6. To determine side bearing preload torque, measure the pulling force of the differential assembly at the drive gear bolt using
Tool.






NOTE:
If pulling force of the differential assembly at the drive gear bolt is within specification, side bearing preload torque will also be
within specification. SEE Disassembly and Assembly.





7. If the pulling force is outside the specification, use a thicker or thinner side bearing adjusting washer to adjust. DLN-
202, "Disassembly and Assembly".






CAUTION:
Select a side bearing adjusting washer for right and left individually.
8. Record the total amount of washer thickness required for the correct side bearing preload torque.