Mine seeps there too!
First with the OEM block off plate. Got new OEM gasket, good for a few months. Leaking again.
Got new OEM oil cooler lines with new OEM gasket. Leaking still.
I'm starting to wonder if it's seeping somewhere (rear main?) and blowing up there..
Or I got crud on the gasket surface when installing it...
Mine too...on both 6.2L engines, in fact. I even went with the ICT billet block-off plate on the '07 (no cooler lines) but am still getting a very slight leak. On the '12 with the cooler lines, there is still slight wetness, but it's way better with the OEM gasket than it was with the Fel-Pro which created a significant leak, so I consider it sealed. If I decide to pull it apart again in the future, I will use the thinnest skim of sealant on it, and see if that helps.
Over 1 yr and 8k miles ago I reinstalled the stock oil blockoff plate w/Felpro# 72435 and a little RectorSeal Tplus2 pipe thread sealant on it. Dry as a bone still.
I use RectorSeal on most gaskets with great results.
my feeling is once you've replaced it with the o'ringed aftermarket one, if it's still leaking. it's probably the oil pan gasket. right behind it is where the oil goes into and out of the oil filter. high pressure area.
mine was still leaking around there even after the bullit plate, I'm sure it's the oil pan on mine. I just don't want to drop the front diff and stuff to replace it. electric steering rack and all in the way too. so I dropped it down about a half inch, put some rtv on the rear corners top and bottom of the gasket and around the 2 holes above where it goes in and out of the filter. it's not perfect, but it went from dripping on the driveway to just being moist everywhere between oil changes. good enough for now.
There’s nothing wrong with the OEM gasket. I’ve installed hundreds of them at this point. You have another leak. Likely oil pan or rear main seal housing.
Good to know on the sealant idea.
In September of 2021, before I bought it in October, the selling Cadillac dealership replaced the oil cooler lines and oil pan gasket with new GM parts.
I have pulled the little round sheet metal inspection cover at the bottom of the bellhousing. I do not see evidence of oil leaking down from the rear main, or radial streaks like oil is being flung off the flexplate.
I have looked up the back side of the block and head as best as I can with a strong light. I do not think the valve cover is leaking.
The leak is a couple of drops on the bottom edge of the oil pan, and some wetness in the area. I am living with it for the moment as I daily drive my Escalade.
When I installed the Fel-Pro gasket, I pulled the oil cooler lines block as far away from the oil pan as I dared so I could wipe the surfaces with a brake cleaner soaked rag. Then hosed the area down with brake cleaner for good measure. Once all was dry, I installed the gasket by hooking it on the bolts installed through the block. I 'think' everything was clean.
I am going to order a Mahle/Clevite gasket and try again.
And or borrow a borescope and try to look at the oil cooler lines block from the top to see if oil is leaking at the top of the block.
Thanks for all the ideas and suggestions!