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Gaskets are an important part of maintaining your vehicle. You’ll know your axle flange gaskets are leaking if you find, or smell, differential fluid near your wheels.



What are Axle Flange Gaskets?

If your vehicle is equipped with a solid rear axle, there’s a good chance you’ll need to replace one or both of your axle flange gaskets eventually.

Axle flange gaskets trap gear oil inside the differential. The wheel hub and outside wheel bearing fit over the ends of the axle. Removing these components is necessary to replace the axle flange gaskets. Wheel bearings should also be inspected and replaced if they show signs of wear.

How do Axle Flange Gaskets Work?

As you drive your car or truck, gear oil makes its way from the differential into the axle housing to lubricate the rest of your axle’s moving parts. Axle flange gaskets keep the wheels and brakes dry by trapping gear oil inside the axle housing. When these gaskets begin to leak, you should notice gear oil near the ends of the axles.

How are Axle Flange Gaskets Made?

Axle flanges are made from a variety of materials, depending on the specific vehicle application. Some vehicles use paper gaskets, while others use injection molded plastic or rubber gaskets.

Why do Axle Flange Gaskets Fail?

  • All seals and gaskets are subject to heat, vibration, oxidation, age, and general wear and tear. It’s perfectly normal for leaks to develop over time.
  • Improper installation is the most common cause of premature gasket failure.

What are the Symptoms of Axle Flange Gasket Failure?

  • Differential fluid is present near the ends of the vehicle’s axle.
  • The differential fluid may read low when checked during routine maintenance.
  • If gear oil contaminates the rear brakes, they may produce smoke under hard braking.

What are the Implications of Axle Flange Gasket Failure

  • Because axle flange gaskets are located near the brakes, it’s important to address any leaks before the brakes become contaminated.
  • Gear oil is expensive, top offs are often cumbersome. Leaking components must be topped off more frequently, which increases the long term operating costs of your vehicle.

If you recently found a puddle of foul smelling goo near the ends of your rear axle, or front axle if you drive a 4x4, leaking axle flange gaskets may be the source of the problem. It’s best to replace axle flange gaskets when you service your wheel bearings.

If you have questions or concerns about axle flange gaskets or any of your vehicle’s components, come into your local Pep Boys where we can answer any question, help you find any part, or perform any vehicle service you might need.