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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. See Differential carrier assembly, description All diagnostics for 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 for easily accessible or visible system components for obvious damage or conditions which may 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. Make sure you are not trying to correct a normal condition.

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 .