Rear Drive Unit (RDU) Assembly Noise

WARNING: This page is about a different car, the 2016 Dodge Journey and 2015 Dodge Journey. However, it is still accessible from the selected car via links, so may be relevant.

The most important part of RDU service is properly identifying the cause of failures and noise complaints. The cause of most RDU failures is relatively easy to identify. The cause of RDU noise is more difficult to identify.

If vehicle noise becomes intolerable, an effort should be made to isolate the noise. Many noises that are reported as coming from the RDU may actually originate at other sources. For example:

Tires
Road surfaces
Wheel bearings
Engine
Transmission
Exhaust
Propeller shaft (vibration)
Vehicle body (drumming)

RDU noises are normally divided into two categories: gear noise or bearing noise. A thorough and careful inspection should be completed to determine the actual source of the noise before replacing the RDU. Other sources of noise from the rear RDU are the pump, actuator, and low hydraulic fluid level.

The rubber mounting bushings help to dampen-out RDU noise when properly installed. Inspect to confirm that no metal contact exists between the RDU case and the body or suspension cradle. The complete isolation of noise to one area requires expertise and experience. Identifying certain types of vehicle noise baffles even the most capable technicians. Often such practices as:

Increase tire inflation pressure to eliminate tire noise.
Listen for noise at varying speeds with different driveline load conditions.
Swerving the vehicle from left to right to detect wheel bearing noise.

All RDU assemblies produce noise to a certain extent. Slight carrier noise that is noticeable only at certain speeds or isolated situations should be considered normal. Carrier noise tends to peak at a variety of vehicle speeds. The pump and actuator may be audible in certain situations that may be normal. Noise is NOT ALWAYS an indication of a problem within the carrier or RDU components.