Automatic Transmission Pinion Seals

Replacement Parts > Transmission Replacements > Gaskets and Sealing Systems

Automatic Transmission Pinion Seals

Filter Options

Important: To get started, click the blue "Filter Options" button to select your vehicle and then use the filters to narrow your options.

Important: To get started, select your vehicle on the left and then use the filters to narrow your options.

What is an Automatic Transmission Pinion Seal?

An Automatic Transmission Pinion Seal is a type of seal used in an automatic transmission system to keep lubricant in and dirt and moisture out. It is located between the transmission's output shaft and the pinion gear.

What is the purpose of an Automatic Transmission Pinion Seal?

The primary purpose of an Automatic Transmission Pinion Seal is to help keep oil and other lubricants in the transmission, while keeping dirt and moisture out. This helps keep the transmission functioning properly and prevents damage due to contamination.

How can I determine if my Automatic Transmission Pinion Seal is faulty?

You can determine if your Automatic Transmission Pinion Seal is faulty by looking for signs of leakage. If you notice any oil or other fluid leaking from the transmission, then it's likely that the Automatic Transmission Pinion Seal is faulty.

Can a faulty Automatic Transmission Pinion Seal cause damage?

Yes, a faulty Automatic Transmission Pinion Seal can cause damage to the transmission. If the seal is not functioning properly, it can allow dirt and moisture to enter the transmission, which can cause damage to the internal components.

How do I replace an Automatic Transmission Pinion Seal?

Replacing an Automatic Transmission Pinion Seal is a fairly straightforward process, but should be done by a professional to ensure it is done properly. Here's a brief overview of the steps involved:

  1. Disconnect the battery and raise the vehicle up on a lift.
  2. Remove the transmission pan and drain the fluid.
  3. Unscrew the bolts connecting the pinion gear to the output shaft.
  4. Remove the old seal and replace it with the new one.
  5. Reattach the pinion gear and tighten the bolts.
  6. Reinstall the transmission pan and refill the fluid.
  7. Reconnect the battery and lower the vehicle.


How often should I inspect my Automatic Transmission Pinion Seal?

It is recommended to inspect the Automatic Transmission Pinion Seal at least once a year, or more often if you notice any signs of leakage or other issues.