Differential Housing Cleaning and Inspection
Differential Housing Cleaning and InspectionHousings
Important: Do not use any type of motored cleaning device, air tools or drills.
1. Carefully and thoroughly inspect all drive unit components before assembly. Thorough inspection of the drive components for wear and stress with subsequent replacement of worn components eliminates costly drive component repair after assembly.
2. Clean the housings in solvent and remove all sealant material from the sealing surfaces.
3. Inspect the clutch and differential housings for the following:
- Damaged sealing surfaces
- Worn or scored bearing race bores
- Damaged bolt, drain plug, or fill plug hole threads
- Porosity
- Damage to the exterior of the housings
- Damaged, restricted or missing vent tube
- Worn mounting bracket bushings
4. Clean and inspect the vent passage (1) and the oil return passage (2).
5. Clean and inspect the vent passage (1) in the rear cover.
6. Clean and inspect the drain plug threads (1), and check the welch plug (2) for leakage, rust holes and looseness.
Gears and Shafts
1. Clean the gears and shafts in solvent.
2. The ring gear and pinion must be inspected for proper wear pattern.
- The end of the gear tooth farthest away from the center of the ring gear (1) is the heel end of the tooth.
- The end of gear tooth nearest to the center of the ring gear (2) is the toe end of the tooth.
- The side of the tooth that curves inward or is concave (3) is considered the coast side of the tooth.
- The side of the tooth that curves outward or is convex (4) is considered the drive side of the tooth.
3. Inspect the pinion shaft for the following:
- Worn or damaged splines (1)
- Worn bearings (2)
- Wear, pitting, or discoloration by heat (3)
- Damaged threads (4)
- Worn or scored shaft (5)
4. Inspect the bearings for a bent bearing cage.
Bearings and Races
1. Inspect the bearing rollers and races for the following:
- Pitting
- Scoring or grooves
- Excessive wear or other damage
Important: Bearing races with any sign of heat discoloration must be replaced.
2. Inspect the bearing rollers and races for heat discoloration. Heat discoloration ranges from a faint yellow to a dark blue color. This discoloration may result from an overload or improper lubrication. Excessive heat causes softening of the rollers and races.
Bearings and Races Clean and Inspect
1. Inspect the bearing rollers and races for the following:
- Pitting
- Scoring or grooves
- Excessive wear or other damage
Important: Bearing races with a sign of hear discoloration must be replaced.
2. Inspect the bearing rollers and races for heat discoloration. Heat discoloration ranges from a faint yellow to a dark blue color. This discoloration may result from an overload or improper lubrication. Excessive heat causes softening of the rollers and races.
3. Inspect the pinion flange sealing surface (1) for wear, damaged bolt threads (2) and worn or damaged splines (3).
Notice: Do not submerge the clutch drum in solvent. This will damage friction material and geroter pump.
Important: The clutch drum is not serviceable. If inoperative conditions are found, replace the unit.
4. Wipe with a clean lint free towel and inspect the following:
- The pinion nut threads (1)
- The pinion splines (2)
- The bearing surface (3)
- The front sealing surface (4)
- The rear sealing surface (5)
5. Clean the differential case in solvent.
6. Inspect the following for cracking or scoring.
- The side bearing mounting surfaces (1)
- The differential pin bores (2)
- The ring gear mounting surfaces (3)
- The side and pinion gear thrust washer 7/16 surfaces (4)
7. Replace the differential carrier assembly as necessary.
8. Clean the following parts in solvent.
9. Inspect the following for scoring, pitted teeth and cracks:
- Side gear thrust washers (1)
- Side gears (2)
- Pinion gear thrust washers (3)
- Pinion gears (4)
- Pinion shaft pin (5)
- Lock pin (6)