Front Final Drive M205
FRONT FINAL DRIVE
Disassembly and Assembly
ASSEMBLY INSPECTION AND ADJUSTMENT
- Drain the differential gear oil before inspection and adjustment.
- Remove and install the carrier cover as necessary for inspection and adjustment.
Total Preload Torque
1.Install the differential side shaft and differential side flange if necessary.
CAUTION:
The differential side shaft and differential side flange must be installed in order to measure total preload torque.
2.Rotate the drive pinion back and forth 2 to 3 times to check for unusual noise and rotation malfunction.
3.Rotate the drive pinion at least 20 times to check for smooth operation of the bearings.
4.Measure total preload torque using Tool.
Tool number ST-3127S000 (J-25765-A)
Total preload torque:Inspection And Adjustment
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.
Runout limit:Inspection And Adjustment
- 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
1.Apply red lead to the 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 drive 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 washer to move 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 washer 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.
Backlash:Inspection And Adjustment
- If the backlash is outside of the specification, adjust each side bearing adjuster.
If the backlash is greater than specification:
Loosen side bearing adjuster A and tighten side bearing adjuster B by the same amount.
If the backlash is less than specification:
Loosen side bearing adjuster B and tighten side bearing adjuster A by the same amount.
CAUTION:
Do not change the side bearing adjusters by different amounts 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.
Runout limit
Companion flange face : Refer to "Inspection and Adjustment"
Companion flange inner side : Refer to "Inspection and Adjustment"
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.Drain the differential gear oil if necessary.
2.Remove the differential side shaft and differential side flange using suitable tool.
3.Remove the extension tube and O-ring from the gear carrier.
CAUTION:
Do not reuse O-ring.
4.Place a small hole in the side oil seal case using suitable tool.
5.Remove the side oil seal using Tool as shown.
Tool number: -SP-8P
6.Remove the carrier cover bolts and separate the carrier cover from the gear carrier using Tool.
Tool number: KV-10111100 (J-37228)
CAUTION:
- Do not damage the mating surface.
- Do not insert flat-bladed screwdriver, this will damage the mating surface.
7.For proper reinstallation, paint matching marks on one side of the side bearing cap and gear carrier.
CAUTION:
- For matching marks, use paint. Do not damage side bearing cap or gear carrier.
- Side bearing caps are line-board during manufacture. The matching marks are used to reinstall them in their original positions.
8.Remove the side bearing caps.
9.Remove the side bearing adjuster.
10.Lift the differential case assembly out of the gear carrier.
CAUTION:
Keep side bearing outer races together with side bearing inner races. Do not mix them up.
11.Remove side bearing inner race using Tools as shown.
Tool number
(A): ST-33081000 (-)
(B): ST-30021000 (-)
CAUTION:
- Do not remove side bearing inner race unless it is being replaced.
- Place copper plates between the vise and the side bearing inner race and drive gear to prevent damage.
- Engage puller jaws in groove to prevent damage to bearing.
- Keep side bearing outer races together with side bearing inner races. Do not mix them up.
12.For proper reinstallation, paint matching marks on the differential case and drive gear.
CAUTION:
Use paint for matching marks. Do not damage differential case or drive gear.
13.Remove the drive gear bolts.
14.Tap the drive gear off the differential case using suitable tool.
CAUTION:
Tap evenly all around to keep drive gear from bending.
15.Remove the lock pin of the pinion mate shaft from the drive gear side using suitable tool.
16.Remove the pinion mate shaft.
17.Turn the pinion mate gear, then remove the pinion mate gear, pinion mate thrust washer, side gear and side gear thrust washer from the differential case.
Drive Pinion Assembly
1.Remove the differential assembly.
2.Remove the 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 the companion flange using suitable tool.
5.Press the drive pinion assembly (with rear inner bearing race and collapsible spacer) out of the gear carrier.
CAUTION:
Do not drop drive pinion assembly.
6.Remove the drive pinion rear bearing inner race and drive pinion height adjusting washer using Tool.
Tool number: ST-30021000 (-)
7.Place a small hole in the front oil seal case using suitable tool.
8.Remove the front oil seal using Tool as shown.
Tool number: -SP-8P
9.Remove the drive pinion front bearing inner race.
10.Remove the drive pinion front bearing outer race using Tool as shown. Locate the driver on the back edge of the drive pinion front bearing outer race, then drive the drive pinion front bearing outer race out.
Tool number
(A): -C-4171
(B): -D-103
CAUTION:
Do not damage gear carrier.
11.Remove the drive pinion rear bearing outer race using Tool as shown. Locate the driver on the back edge of the drive pinion rear bearing outer race, then drive the drive pinion rear bearing outer race out.
Tool number
(A): -C-4171
(B): -C-4307
CAUTION:
Do not damage gear carrier.
INSPECTION AFTER DISASSEMBLY
Clean the disassembled parts. Then inspect the parts for wear or damage. If wear or damage are found, 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. Exploded View
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.)
Side gear back clearance: Refer to "Inspection and Adjustment"
- If the side gear back clearance is outside of the specification, use a thicker or thinner side gear thrust washer to adjust.
Inspection And Adjustment.
If the side gear back clearance is greater than specification:
Use a thicker side gear thrust washer.
If the side gear back clearance is less than specification:
Use a thinner side gear thrust washer.
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.
Drive Pinion Height
- Drive gear and drive pinion are supplied in matched sets only.
Matching numbers on both drive pinion and drive gear are etched for verification. If a new gear set is being used, verify the numbers of each drive pinion and drive gear before proceeding with assembly.
- The mounting distance from the centerline of the drive gear to the back face of the drive pinion for the M205
final drive assembly is 103.5 mm (4.0748 inches).
On the button end of each drive pinion, there is etched a plus (+) number, a minus (-) number, or a zero (0), which indicates the best running position for each particular gear set. This dimension is controlled by a selective drive pinion height adjusting washer between the drive pinion rear bearing inner race and drive pinion.
For example: If a drive pinion is etched m+8 (+3), it would require 0.08 mm (0.003 inch) less drive pinion height adjusting washer than a drive pinion etched "0". This means decreasing drive pinion height adjusting washer thickness; increases the mounting distance of the drive pinion to 103.6 mm (4.0778 inches). If a drive pinion is etched m-8 (-3), it would require adding 0.08mm (0.003 inch) more to the drive pinion height adjusting washer than would be required if the drive pinion were etched "0". By adding 0.08 mm (0.003 inch), the mounting distance of the drive pinion was decreased to 103.4 mm (4.0718 inches) which is just what a m-8 (-3) etching indicated.
- To change the drive pinion height, use different drive pinion height adjusting washers which come in different thickness.
- Use the following tables as a guide for selecting the correct drive pinion height adjusting washer thickness to add or subtract from the old drive pinion height adjusting washer.
ASSEMBLY
Drive Pinion Assembly
1.Install drive pinion rear bearing outer race using Tools.
2.Install drive pinion front bearing outer race using Tools.
3.Select drive pinion height adjusting washer. Inspection And Adjustment.
4.Install the selected drive pinion height adjusting washer to the drive pinion. Press the drive pinion rear bearing inner race to it using Tool.
CAUTION:
Do not reuse drive pinion rear bearing inner race.
5.Install the collapsible spacer to the drive pinion.
CAUTION:
Do not reuse collapsible spacer.
6.Apply differential gear oil to the drive pinion rear bearing, and install the drive pinion assembly to the gear carrier.
7.Apply differential gear oil to the drive pinion front bearing, and install the drive pinion front bearing inner race to the drive pinion assembly.
CAUTION:
Do not reuse drive pinion front bearing inner race.
8.Apply multi-purpose grease to the lips of the new front oil seal.
Then drive the new front oil seal in evenly using Tools.
CAUTION:
- Do not reuse front oil seal.
- Do not incline the new front oil seal when installing.
- Apply multi-purpose grease to the lips of the new front oil seal.
9.Install the companion flange to the drive pinion while aligning the matching marks. Tap the companion flange until fully seated using suitable tool.
10.Apply anti-corrosive oil to the threads of the drive pinion and the seating surface of the new drive pinion lock nut. Then adjust the drive pinion lock nut tightening torque using suitable tool (A), and check the drive pinion bearing preload torque using Tool (B).
CAUTION:
- Do not reuse drive pinion lock nut.
- Apply anti-corrosive oil to the threads of the drive pinion and the seating surface of the new drive pinion lock nut.
- Adjust the drive pinion lock nut tightening torque to the lower limit first. Do not exceed the drive pinion lock nut specified torque. Exploded View.
- If the drive pinion bearing preload torque exceeds the specified value, replace collapsible spacer and tighten it again to adjust. Do not loosen drive pinion lock nut to adjust the drive pinion bearing preload torque.
- After adjustment, rotate drive pinion back and forth 2 to 3
times to check for unusual noise, rotation malfunction, and other malfunctions.
11.Check companion flange runout. Inspection And Adjustment.
12.Install the differential case assembly. Exploded View.
Differential Assembly
1.Install side gear thrust washers with the same thickness as the ones installed prior to disassembly, or reinstall the old ones on the side gears.
2.Install the side gears and side gear thrust washers into the differential case.
3.Install the pinion mate thrust washers to the two pinion mate gears. Then install the pinion mate gears with the pinion mate thrust washers by aligning them in diagonally opposite positions and rotating them into the differential case.
4.Install the pinion mate shaft and align the lock pin hole on the pinion mate shaft with the lock pin hole on the differential case.
5.Measure the side gear end play. If necessary, select the appropriate side gear thrust washers. Inspection And Adjustment.
6.Drive a new lock pin into the pinion mate shaft until it is flush with the differential case using suitable tool.
CAUTION:
Do not reuse lock pin.
7.Align the matching mark of the differential case with the mark of the drive gear, then place the drive gear onto the differential case.
8.Install and tighten the new drive gear bolts to the specified torque. Exploded View.
CAUTION:
- Make sure the drive gear back and threaded holes are clean.
- Do not reuse drive gear bolts.
- Tighten new drive gear bolts in a crisscross pattern.
9.Press the new side bearing inner races to the differential case
CAUTION:
Do not reuse side bearing inner races.
10.Install side bearing adjusters into gear carrier.
11.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).
12.Install the side bearing caps with the matching marks aligned.
NOTE:
Do not tighten at this step. This allows further tightening of side bearing adjusters.
13.Tighten each side bearing adjuster alternately turning drive gear.
14.Check and adjust tooth contact, backlash, drive gear runout and total preload torque. Inspection And Adjustment.
Recheck above items.
- After adjusting tooth contact and backlash secure side bearing adjuster with screws and tighten side bearing cap bolt to the specified torque. Exploded View.
15.Apply multi-purpose grease to the lips of the new side oil seal. Then drive the new side oil seal in evenly to the gear carrier using suitable tool.
CAUTION:
- Do not reuse side oil seal.
- Do not incline the new side oil seal when installing.
- Apply multi-purpose grease to the lips of the new side oil seal.
16.Install the extension tube with a new O-ring.
CAUTION:
- Do not reuse O-ring.
- If the extension tube is being replaced, install a new differential side shaft bearing.
17.Apply 3 mm (0.12 in) bead of sealant to the mating surface of the carrier cover as shown.
- Use Genuine Silicone RTV or equivalent. Recommended Chemical Products And Sealants.
CAUTION:
Remove any old sealant adhering to the mating surfaces.
Also remove any moisture, oil, or foreign material adhering to the application and mating surfaces.
18.Install the carrier cover to the gear carrier. Tighten the bolts to the specified torque. Exploded View.
19.Install differential side shaft and differential side flange.