1st time digging into an ls. Long time sbc/bbc guy. I know just crawled from under a rock..question - you think this this was the rear main seal or a cover gasket? Oil seems flung everywhere. Going to replace all but strange.. l94 out of a 2012 Yukon. 6.2.

 

Rear main seal leak typically throws oil forward, whereas a cover gasket leak tends to drip downward. Given the oil is "flung everywhere", it's likely the rear main seal.

 

Replace the rear main seal. If you're already planning to replace all seals, that's a good opportunity to do it.

 

Installing a new main seal on a LS is a piece cake. It comes with a plastic "installer" thing so alignment is super easy.

 

You can buy a NEW cover with the seal ALREADY IN IT, and a new cover gasket comes with it, for LESS THAN the price of a seal and a gasket.

Don't bother "replacing the seal". Replace the COVER.

Note that those 2 long 6mm bolts that go all the way through the pan and up into the cover, VERY OFTEN get stripped. I highly recommend putting HeliCoils into your new cover.

I also recommend HeliCoils for the bolt holes that hold on the oil cooler lines or the adapter plate thing, whichever that motor will be getting; and if it's the cover plate, get a new one, because Stimpy has probably already overtightened the bolts and distorted any used one you may come across.

Be sure to use thread sealer (NOT silicone) on the converter bolt threads, since those look right directly into the crankcase.

 

Thanks guys for all the input! I got an alignment tool so I opted for the seal and gasket .. probably would have been better off with the full cover but figured to get it centered right the tool would be more accurate than I would.. Motor only has 115k on it surprised the seal went out�

 

Now is a good time to put a Sac City oil barbell in it when you replace the rear seal.

 

I tore it apart, and yes I got an aluminum barbell for it - thanks for the suggestion!! And it turns out to be an l92. Super sludge on the inside of the motor. Buyer beware. It was out of a 2012 Yukon Denali.?? Pulled the lifters and valley tray .. no dod.. wonder if the motor was original to the truck?

 

No DOD/AFM on L92. Yes on VVT.