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Symptoms of a Bad or Failing Pinion Seal


The pinion seal is located inside differentials of vehicles. The pinion seal is located near the pinion shaft and is designed so that fluid does not leak out of the differential. Some vehicles have a rear pinion seal, where others have both a front and rear pinion seal, it just depends on the make and model of your vehicle and if the vehicle has rear or four wheel drive. Over time, the rubber on the pinion seal wears down and the seal will not be effective as it was before. Each time your vehicle is serviced, the pinion seal should be inspected to ensure there are no symptoms of a bad or failing pinion seal.

1. Leaking pinion seal

One of the biggest signs your pinion seal is failing is it is leaking. To check for a leak, follow the drive shaft to the rear axle, then look around the yoke for fresh oil. If you notice fresh oil, you have a pinion seal leak. As soon as you notice this, contact the professionals at YourMechanic to have the pinion seal replaced.

2. Differential has low fluid

If you notice your differential has low fluid, chances are it is leaking from the pinion seal. This needs to be fixed in a timely manner because as the fluid levels drop, the gears will wear down as the friction increases. Without a proper working differential, your vehicle will not be able to be driven. Furthermore, a pinion seal is a relatively straightforward repair, but if you wait too long, it will become more extensive once you start adding in various parts such as the differential.

3. Whining noise

Low fluid in the differential is normally shown by a whining noise while the vehicle is in motion. This noise could mean a pinion seal leak, or it could be another problem with your vehicle’s differential. A professional from YourMechanic will be able to diagnose the problem and have your vehicle repaired in a short amount of time.

As soon as you notice a leaking pinion seal, constant low fluid in your differential, or a whining noise while you are driving, book a service online 24/7 with YourMechanic to have your pinion seal looked at. This is an important part of keeping your vehicle properly maintained and running correctly. In addition, by repairing the problem early, you will be able to save your differential which can save you time and money in the long run.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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