Not Sure If Your Rear Main Seal Is Leaking?

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Larryjb

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@Larryjb -- did yours look like this?

Hmm, look like what? Do you mean your previous picture from May 10?

The only way I was able to conclude that my rear main was leaking was to replace the oil pan gasket (which I knew was leaking) by the book. I did everything by the book: specified RTV at the corners, torqued everything exactly as instructed, etc. I cleaned the gasket surfaces very carefully so as to not score the mating surface. I had found a ridge which I smoothed off, and added a dab of RTV to.

When I still had a leak, I figured it had to be the rear main. Unless you have a really good boroscope, there is no way you can see well enough behind the flexplate. You won't be able to properly see all the rear main cover and rear main. Once I got my tranny out, I could clearly see where things had been leaking, and the worst leaking was in fact the rear cover.

If you leak is worse after doing the oil pan, you may want to redo it making sure everything is done by the book. Somewhere I do have a thread on this, but I can't remember if it was with my rear main oil seal thread or not.

Good luck!
 

mattbta

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Yeah, both jonnytahoe and my pictures.

The cheapo amazon special camera I used a year ago was worthless. I can't pinpoint exactly when it got worse but this was the second or third time I dropped the pan (new gasket every time) and i used copious RTV. Guess I'll just take it in for diagnosis/repair as I have zero interest in pulling the transmission myself. Thanks for documenting your journey on all of these things though.
 

OR VietVet

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Yeah, both jonnytahoe and my pictures.

The cheapo amazon special camera I used a year ago was worthless. I can't pinpoint exactly when it got worse but this was the second or third time I dropped the pan (new gasket every time) and i used copious RTV. Guess I'll just take it in for diagnosis/repair as I have zero interest in pulling the transmission myself. Thanks for documenting your journey on all of these things though.

Too much, "copious", RTV is bad and causes problems with oil pick up. Needs just a dab here and there in just the right places. I think I know what you were saying but wanted to say it for other members who have not had the fun of replacing the oil pan gasket.

I just did them both at the same time. No doubt I got all leaks. While under there for the work I am doing in my build/construction thread, I can see nothing but dry. Well, that and all the new parts I am bolting on.
 
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JonnyTahoe

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Yeah, both jonnytahoe and my pictures.

The cheapo amazon special camera I used a year ago was worthless. I can't pinpoint exactly when it got worse but this was the second or third time I dropped the pan (new gasket every time) and i used copious RTV. Guess I'll just take it in for diagnosis/repair as I have zero interest in pulling the transmission myself. Thanks for documenting your journey on all of these things though.
Nobody could have much interest in removing the trans themselves but being able to do it yourself gives a person much satisfaction being it is one of the most time consuming and labor intensive jobs you will ever do to your Truck.
 

Larryjb

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Yeah, both jonnytahoe and my pictures.

The cheapo amazon special camera I used a year ago was worthless. I can't pinpoint exactly when it got worse but this was the second or third time I dropped the pan (new gasket every time) and i used copious RTV. Guess I'll just take it in for diagnosis/repair as I have zero interest in pulling the transmission myself. Thanks for documenting your journey on all of these things though.

Also, where exactly did you use the RTV? What RTV did you use? (Did you use the one with maximum oil resistance?)
 

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