Visual/Physical Inspection
WARNING: This page is about a different car, the 2002 Pontiac Montana, 2002 Oldsmobile Silhouette, and 2002 Chevrolet Venture. However, it is still accessible from the selected car via links, so may be relevant.
- Inspect for aftermarket devices, which could affect the operation of the vehicle. Refer to CHECKING AFTERMARKET ACCESSORIES .
- Inspect the easily accessible or visible system components for obvious damage or conditions, which could cause the symptom.
- Check for the correct lubricant level and the proper viscosity.
- Verify the exact operating conditions under which the 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 condition.
- Inspect for all-wheel drive activation 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 Antilock 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 condition
- An inoperative or "stuck" clutch pump check valve
- A defective rear differential assembly
- An inoperative transfer case assembly