- Symptoms - Rear Drive Axle

DIAGNOSTICS SYMPTOMS - REAR DRIVE AXLE

STRATEGY BASED DIAGNOSTICS
Review the system operations in order to familiarize yourself with the system functions. 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 problem. The diagnostic flow is the place to start when repairs are necessary.

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 condition which could cause the symptom.
^ Verify the exact operating conditions under which the concern exists. Note factors such as 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.

NOTICE: Do not exceed more that 5 seconds of parking brake apply. RDM damage may result.

^ Rear axle activation and operation may be checked by positioning the four wheels off the ground, starting the vehicle, and selecting the "drive" position. A properly operating rear axle and transfer case will rotate all four wheels at equal rpm. Fully apply the parking brake, the rear will stop turning. Apply throttle while watching the rear wheels. They will rotate slightly as the driveline winds up. This indicates the AWD is functioning.
^ Factors that may contribute to an inoperative rear axle include:
- Low gear oil levels
- A mini spare or different size tires
- A fluid over-temperature condition
- A defective rear axle assembly
- An inoperative transfer case assembly
- Wrong fluid type

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

NOISE ACCEPTABILITY
A gear driven unit will produce a certain amount of noise. Some noise is acceptable and audible at certain speeds, or under various driving conditions such as a newly paved blacktop road. Slight noise is not detrimental to the operation of the axle and is considered normal.

SYMPTOM LIST
Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom.
^ Noisy in Drive
^ Noisy when Coasting
^ Intermittent Noise
^ Constant Noise
^ Noisy on Turns
^ Rear Axle Lubricant Leak Diagnosis