What is an axle shaft seal?
A seal is a soft rubber or plastic part that slides over the smooth section of the axle shaft. It forms a barrier that stops grit from getting into the axle, while keeping the transmission fluid or axle fluid where it belongs.
If the seal leaks, the fluid leaks out of the axle and your transmission will struggle.
Should I replace my axle shaft seal?
You probably don’t think about the axle shaft until you suspect something is wrong. Here are signs that the axle shaft seal needs to be replaced:
Differential fluid or transmission fluid leaks
below your vehicle near the front wheels: You might notice these under your car after it’s been parked. If you spot fluid leaks, get your car inspected as soon as possible.The transmission slips when you drive on the highway: Axle seals leak more when you’re driving fast. If too much fluid has leaked, your transmission will start to slip when you’re driving at high speed.
Your car makes noises when you make a turn. Listen for knocking or clicking, which are signs that the seal is worn out.
You notice excessive vibration: If the seal wears out, the axle shaft can loosen and vibrate.
Keep in mind: Axle shaft seals can be tricky to diagnose unless you know what you’re looking for. Take your vehicle in for an inspection at the first sign of a problem.
How often should an axle shaft seal be replaced?
Ideally, axle shaft seals should last the life of the vehicle—they only need to be replaced if they leak (typically because they were improperly installed).
Is an axle shaft seal hard to replace?
Replacing axle seals requires advanced automotive knowledge because you’ve got to remove the CV axle and some of the wheel hub assembly. You’ll also have to drain transmission fluid or differential oil before you remove the axle. Plus, you’ll need specialized tools to carry out the replacement. It’s a good idea to leave this one to the professionals.