Intermittent
Test the vehicle under the same conditions that the customer reported in order to verify the system is operating properly.
Noisy in Drive
| Cause | Correction |
|---|---|
| Inspect for the proper transaxle and gear oil levels prior to performing system diagnosis. | |
| Low gear oil level | Inspect the transfer case for leaks, repair as required. Refer to Transfer Case Leak Diagnosis , and Adhesives, Fluids, Lubricants, and Sealers . |
| Incorrect gear oil in the transfer case | Replace the gear oil. Refer to Adhesives, Fluids, Lubricants, and Sealers . |
| Water or contamination within the lubricant | Replace the lubricant and flush the transfer case of the contaminated fluid. |
| Worn propeller shaft constant velocity joints | Replace propeller shaft assembly. Refer to Propeller Shaft Replacement . |
| Worn or noisy wheel bearings | Replace the wheel bearings as required. |
| Worn axle shaft constant velocity joints | Replace the constant velocity joints, as required. |
| Worn bearing in the differential assembly | Repair or replace the assembly. |
| Bearing noise within the transfer case A grinding noise that occurs at a specific engine speed, regardless of transmission gear, is not within the transfer case. A grinding noise that changes as a transmission shift occurs is not within the transfer case. A grinding noise that changes as vehicle speed changes may be also caused by worn wheel bearings. A grinding noise that changes as the vehicle turns may also be caused by worn wheel bearings and/or tires. | Inspect for the proper fluid level. Fill, as required. Identify the location of the noise using the J 39570 Chassis Ears. If the noise continues, repair or replace components, as required. |
| Gear set whine noise within the transfer case A whine noise that occurs at a specific engine speed, regardless of transmission gear, is not within the transfer case. A whine noise that changes as a transmission shift occurs is not within the transfer case. A whine noise that changes as vehicle speed changes may be also caused by worn wheel bearings. A whine noise that changes as the vehicle turns may also be caused by worn wheel bearings and/or tires. | Inspect for the proper fluid level. Fill, as required. Identify the location of the noise using the J 39570 Chassis Ears. If the noise continues, repair or replace components, as required. |
Noisy in Drive
Noisy When Coasting
| Cause | Correction |
|---|---|
| Inspect for the proper transaxle and gear oil levels prior to performing system diagnosis. | |
| Low gear oil level | Inspect the transfer case for leaks, repair as required. Refer to Transfer Case Leak Diagnosis , and Adhesives, Fluids, Lubricants, and Sealers . |
| Incorrect gear oil in the transfer case. | Replace the gear oil. Refer to Adhesives, Fluids, Lubricants, and Sealers . |
| Worn propeller shaft constant velocity joints | Replace the propeller shaft assembly. Refer to Propeller Shaft Replacement |
| Worn axle shaft constant velocity joints | Replace the constant velocity joints, as required. |
| Worn bearing in the differential assembly | Repair or replace the assembly as required. |
| Bearing noise within the transfer case A grinding noise that occurs at a specific engine speed, regardless of transmission gear, is not within the transfer case. A grinding noise that changes as a transmission shift occurs is not within the transfer case. A grinding noise that changes as vehicle speed changes may be also caused by worn wheel bearings. A grinding noise that changes as the vehicle turns may also be caused by worn wheel bearings and/or tires. | Inspect for the proper fluid level. Fill, as required. Identify the location of the noise using the J 39570 Chassis Ears. If the noise continues, repair or replace components, as required. |
| Gear set whine noise within the transfer case A whine noise that occurs at a specific engine speed, regardless of transmission gear, is not within the transfer case. A whine noise that changes as a transmission shift occurs is not within the transfer case. A whine noise that changes as vehicle speed changes may be also caused by worn wheel bearings. A whine noise that changes as the vehicle turns may also be caused by worn wheel bearings and/or tires. | Inspect for the proper fluid level. Fill, as required. Identify the location of the noise using the J 39570 Chassis Ears. If the noise continues, repair or replace components, as required |
Noisy When Coasting
Transfer Case Housing
- Clean the front case half in cleaning solvent and air dry.
- Inspect the housing for the following: Damage to threaded bolt holes (1 and 2) Damaged sealing surfaces (3) Bearing races (5) with wear or pitting Porosity External Damage
Rear Extension Housing
- Clean the rear case half in cleaning solvent and air dry.
- Inspect the housing for the following: Damages sealing surfaces (1) Damage to threaded bolt holes (2) Bearing races (3) with wear or pitting Porosity External Damage
Input Shaft
- Clean the input shaft in cleaning solvent.
- Inspect the input shaft splines (1) for excessive wear or damage.
- Inspect the input shaft seal surfaces (2 and 5) for excessive grooves, rust, pitting or other damage.
- Inspect the input shaft gear teeth (4) for excessive wear or damage.
Idler Gear and Idler Shaft
- Clean the idler shaft in cleaning solvent.
- Inspect the idler shaft seal surfaces (8) for excessive grooves, rust, pitting or other damage. - Model Dependent
- Inspect the sealing surfaces of the idler gear shaft (5) for excessive grooves, rust, pitting or other damage. - Model Dependent
- Inspect the idler shaft gear teeth (3 and 4) for excessive wear or damage
- Inspect the bearings (2 and 6) for pitting, wear or other damage.