Rear main seal

Peeledpeas said:

I just replaced my rear main seal while I was swapping the transmission a couple months ago but it appears to be leaking already. Is there anything else that could leak that might look like a rear main leak? I can definitely see a stream of oil comin down behind the flex plate. I'm pretty sure I got a good look at the oil pressure sensor and it doesn't appear to be leaking. Kinda really annoyed about this. Was a Felpro seal set with cover gasket and I followed the instructions. 2005 GMC Yukon 5.3L

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Peeledpeas said:

I just replaced my rear main seal while I was swapping the transmission a couple months ago but it appears to be leaking already. Is there anything else that could leak that might look like a rear main leak? I can definitely see a stream of oil comin down behind the flex plate. I'm pretty sure I got a good look at the oil pressure sensor and it doesn't appear to be leaking. Kinda really annoyed about this. Was a Felpro seal set with cover gasket and I followed the instructions. 2005 GMC Yukon 5.3L

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justirv said:

Installation of a LS rear main seal can be problematic. Did you use any type of alignment or installation tool? Something like the Sac City tool, which will align the cover and seal to the block. If you find this (rear seal) is the problem, I highly recommend one. Good luck.

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drdave81 said:

Yep, if you didn't use the alignment tool, the trans is likely coming back out. Gonna have to redo it unfortunately.

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Peeledpeas said:

I was unaware of needing an alignment tool. There was a round plastic thing that came in the Felpro set but I take that may have been inadequate for the task?

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