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Q: The rear main seal leaking off a '99 F-150 4.6

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I have a '99 F-150 4.6. The rear main seal has been leaking a little off the truck. It has 310,000 miles. Is it an easy fix? Should I change the transmission seal on it too?

A: The actual fix of taking the seal in and ou...

The actual fix of taking the seal in and out once you are there is easy, but the problem is that you’ve got to move the transmission off to get to it.

So, if you are willing to do that, you might as well change the transmission seal while you are in there. Now, I had very good luck with this product AT-205 re-seal. They sell it on Amazon and I buy it all the time.

You pour it in the engine oil or in the transmission oil. It’s a polymer so it mixes with both and it can rejuvenate a bad rear or front main seal. You might just try that first. If you would like help from a professional, a technician from YourMechanic can come to your home or office to find and repair your transmission fluid leak.

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