Signs Your Differential Is Failing

The differential assembly is designed to transfer power from the engine to the wheels. When the vehicle is cornering, the differential also allows the inner and outer drive wheels to turn at different speeds to prevent scuffing.

Signs of a failing differential

A faulty differential can cause many problems. These are some of the most common:

• Noise: Failing differentials can make a variety of noises, from rattling due to broken gear teeth, to whining noises from bad bearings.
• Leaks: Most differential leaks are caused by worn seals. But in some cases, excessive bearing play, which allows internal components to move and cause seal damage, can create leaks.
• Shudder and vibration: A faulty differential may cause a shudder or vibration. The problem may be more noticeable when cornering.
• Vehicle won’t move: If the differential fails completely, power can’t be transferred to the drive wheels and you’re stuck with a vehicle that won’t move.

How to fix the problem

If you suspect a differential problem, the first step is to have the vehicle diagnosed by a professional. Other issues, such as driveshaft problems and worn tires, can mimic a bad differential.

In many instances, a failing differential can be rebuilt. But if there’s catastrophic damage, or metal debris has circulated throughout the unit, replacement may be needed. Both replacement and rebuilding are quite involved, so the repair is best left to a professional.