How Do I Fix A Rear Main Seal Leak?

Replacing a rear main seal is a big job. Your car or truck engine has a lot of seals to keep engine oil in its proper passages and from leaking out (as you know we have an oil leak sealant for many of these problems). The rear main seal is the rear seal for the crank shaft in your engine. It’s a very important seal since it is so low on the engine a significant amount of oil can quickly leak from it allowing your engine oil levels to get dangerously low before you have time to add more oil.

The rear main seal is also one of the most difficult seals on an engine to replace. Since it seals the crank shaft and is at the rear of the motor, the transmission will need to be removed to get to the rear main seal and in most cases the crank shaft will also need to be removed. Many mechanics will not replace the rear main seal in a motor without removing the motor from the vehicle and doing at least a partial rebuild.

Letting your rear main seal continue to leak also can be detrimental to your vehicle’s continued operation. Besides having a low oil level, the leaking oil will be spread on the underside of your car as you drive. Not only is this messy and difficult to clean up, the oil can get onto your exhaust system causing it to burn which can be a fire hazard and cause an unpleasant odor.

Why does a rear main seal start to leak?

Normal Wear and use
Sealing material compressing over time
Improper installation after a rebuild

The best way to repair a rear main seal is to recondition the seal that is currently in your vehicle. BlueDevil Rear Main Sealer works to swell the rear main seal in your car stoping the leak. BlueDevil Rear Main Sealer can extend the life of the current seals bringing your vehicle back to safe operation and saving you money!

You can purchase BlueDevil Rear Main Sealer directly from the manufacturer here: Transmission Sealer, or at your local parts stores: