Begin the system diagnosis by reviewing the Differential Carrier Assembly Disassembled Views and the Differential Carrier Assembly Description in Rear Drive Axle, and Transfer Case Description in Transfer Case - NVG 900. Reviewing the description and operation information will help you determine the correct symptom diagnostic procedure when a malfunction exists. Reviewing the description and operation information will also help you determine if the condition described by the customer is normal operation. Refer to Symptoms - Rear Drive Axle in order to identify the correct procedure for diagnosing the system and where the procedure is located.