Visual/Physical Inspection
- Inspect for aftermarket devices, which could affect the operation of the vehicle.
- Inspect the easily accessible or visible system components for obvious damage or conditions, which could cause the symptom.
- Check for the correct lubricant level ad the proper viscosity.
- Verify the exact operating conditions under which thee concern exists. Note factors such as vehicle speed, road conditions, ambient temperature, and other specifics.
- Compare the driving characteristics or sounds (if applicable) to a known good vehicle and make sure you are not trying to correct a normal conditions.
- Inspect for all-wheel drive activations and operation, Refer to ALL-WHEEL DRIVE (AWD) SYSTEM FUNCTIONAL INSPECTION .
- Factors that may contribute to an inoperative rear differential include:
- Low gear oil levels
- Differential inoperative due to Anti-lock Brake System (ABS) function
- Inoperative Powertrain Control Module (PCM) and/or Wiring System
- A mini spare or different size tire installed
- A fluid over-temperature conditions
- An inoperative or "Stuck" clutch pump check valve
- A defective rear differential assembly
- An inoperative transfer case assembly