6.2 L92 rear main seal

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Tunzafun502

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I'm thinking I have a bad rear main seal on my 07 Yukon Denali. I have a leak towards the rear of the engine, between the engine and bell housing. I've never replaced one before and am looking for insight on how to do this. I'm not very mechanically inclined, unfortunately, but am willing to give it a shot. I appreciate any input.
 

Rocket Man

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If it is indeed the rear main seal leaking, the transmission needs to be removed. Not something you’d want to do if you’re not mechanically inclined. First you need to be sure that’s the problem because it’s a $25 part but for a shop to do it, you’re looking at most likely $1500 in labor if not more. There are other places for leaks that could result in oil dripping in that area. One is the oil pressure sender. Another is rocker covers. The other that comes to mind is the valley cover. I might be forgetting one, others will chime in. It can be difficult to determine where a leak originates from, it can run down from above. You can start by cleaning the block with a pressure washer and degreaser and then get a borescope and inspect after you run the engine a bit. The sender is pretty inexpensive, you could try replacing it as well as the rocker cover gaskets and see if anything changes. The valley cover is kind of hard to tell but if you look with the borescope at the rear of the block near the firewall you might be able to tell. Others here have dealt with a valley cover leak. Good luck, let’s hope it’s not the rear main.
 

OR VietVet

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Welcome to the forum and your first post.

IMO, if I was you and not having mechanical abilities and therefore likely not having all the tools and equipment for the job, I would not attempt it.

I was in the field 35+ years and have no lift or trans jack or even a smooth surface to lay on to work off of and I would think twice before doing it. If I was you, I would watch a minimum of 5 you tube videos before even thinking about it. I say 5 videos because some people work smarter than others and have different experience and capabilities and tools.
Good luck. If you have a shop you trust, use them. If you don't, ask a friend(s). Also, ask if you can supply parts and insist on Genuine GM parts if they ask what you want used. Or Fel-Pro is a good choice too.



 

m1dn

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Check the tranny cooler lines, i had leak around the same area.

Turned out tranny cooler line gasket leaking, replacing one this week.
My first though was also rear main seal, but after watching couple of vids explaining where and how it would leak i removed the plate/cover where the oil was dripping from and it was clean n dry inside.
Started looking around further more closely and turned out oil was just end up on this plate dripping all the way from the cooler lines and you could see bunch of oil bubbling up right at the gasket
 

donjetman

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I'm thinking I have a bad rear main seal on my 07 Yukon Denali. I have a leak towards the rear of the engine, between the engine and bell housing. I've never replaced one before and am looking for insight on how to do this. I'm not very mechanically inclined, unfortunately, but am willing to give it a shot. I appreciate any input.
I'm a DIYer and did the rear main seal on our 07 Yukon Denali 6.2 L92 four yrs ago.
Here's the link of the thread I did: https://www.tahoeyukonforum.com/threads/rear-main-seal-job-pan-etc-07-yukon-denali-6-2.108334/
 

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