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Symptoms - Rear Differential Carrier

Symptoms - Rear Differential Carrier

Strategy Based Diagnostics

Review the system operation in order to familiarize yourself with the system functions. Refer to Differential Carrier Assembly Description . All diagnosis on a vehicle should follow a logical process. Strategy based diagnostics is a uniform approach for repairing all systems. The diagnostic flow may always be used in order to resolve a system condition. The diagnostic flow is the place to start when repairs are necessary. For a detailed explanation, refer to Strategy Based Diagnosis .

Visual/Physical Inspection


• 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 and sound (if applicable) with a vehicle known to be in good condition. Ensure you do not try to correct a normal state.

• Inspect for all-wheel drive activation and operation.

Factors that may contribute to an inoperative rear differential include:

- Low gear oil levels

- Differential inoperative due to antilock brake system (ABS) function

- Inoperative engine control module (ECM) 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

• Sometimes it might be difficult to judge whether the noise is coming from the propeller shaft or rear differential carrier assembly. Refer to Symptoms - Propeller Shaft .


Intermittent

Test the vehicle under the same conditions that the customer reported in order to verify the system is operating properly.

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:


• Propeller Shaft-Refer to Symptoms - Propeller Shaft .

• Wheel Drive Shafts-Refer to Symptoms - Wheel Drive Shafts .

• Vibration Diagnosis and Correction-Refer to Symptoms - Vibration Diagnosis and Correction .