Rear main seal leak? Pics attached

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Blackcar

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My 02 Tahoe (285K mi) rains oil. This thread affirms my suspicion of the RMS. With oil at $8 a qt, I need to do something about it soon. New to Atlanta area and few tools, unfortunately. Anyone know anyone in the area who'll rent me their shop stall or garage (with tools)??

I'm also concerned about the oil flashing into a fire as it smolders on the exhaust crossover section. Has anyone seen this happen? Should I install a heat wrap on this section of exhaust until I make the needed repair?
Have you looked at valley plate seal and oil pressure sending unit at back of engine close to firewall picture to me look like oil coming down side of trans bell housing.
 

Logani

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Have you looked at valley plate seal and oil pressure sending unit at back of engine close to firewall picture to me look like oil coming down side of trans bell housing.
Yes. Recently replaced knock sensors (and OP sending unit because it was accessible) as well as valve cover gaskets. Was clean in that area. I'll be redoing the job - see my other posts today - and will check it out again. I'm having to add 1.5 qts for every tank of gas. It's embarrassing.
 

Logani

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On second thought, after seeing Davids vids, this could actually be my problem. I may have overlooked it when I had the intake off to replace the knock sensors. I don't think I went that far back (and down) because I wasn't actually looking for it: just a general look-over and a OP sending unit swap. Good stuff. It just seems like more than a rms and the valley plate seal would explain it. Is there pressure behind it or just lots of splashing around?
 

donjetman

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gen4 knock sensors are on the side of the block and they can't cause an oil leak.
 

89Suburban

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On second thought, after seeing Davids vids, this could actually be my problem. I may have overlooked it when I had the intake off to replace the knock sensors. I don't think I went that far back (and down) because I wasn't actually looking for it: just a general look-over and a OP sending unit swap. Good stuff. It just seems like more than a rms and the valley plate seal would explain it. Is there pressure behind it or just lots of splashing around?


If you have DOD/AFM the valley cover does have pressure in it.
 

91RS

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Yes. Recently replaced knock sensors (and OP sending unit because it was accessible) as well as valve cover gaskets. Was clean in that area. I'll be redoing the job - see my other posts today - and will check it out again. I'm having to add 1.5 qts for every tank of gas. It's embarrassing.

You have oil consumption, not a leak. If you were leaking 1.5 quarts of oil every tank of fuel (300 miles or so), the entire underside of your truck would be drenched in oil and your driveway would be black. You could take it to Canada and it would never rust.
 
OP
OP
M

m1dn

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If you have DOD/AFM the valley cover does have pressure in it.
Wouldn’t it have pressure without dod anyway since oil pressure sensor is there? Mine is without dod but was pissing oil everywhere around the cover
 

Blackcar

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On second thought, after seeing Davids vids, this could actually be my problem. I may have overlooked it when I had the intake off to replace the knock sensors. I don't think I went that far back (and down) because I wasn't actually looking for it: just a general look-over and a OP sending unit swap. Good stuff. It just seems like more than a rms and the valley plate seal would explain it. Is there pressure behind it or just lots of splashing around?
If you're talking about oil pressure sender there is no pressure if engines off but will leak when running.
 

Logani

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You have oil consumption, not a leak. If you were leaking 1.5 quarts of oil every tank of fuel (300 miles or so), the entire underside of your truck would be drenched in oil and your driveway would be black. You could take it to Canada and it would never rust.
I didn't exaggerate. Will post pictures of my well-preserved undercarriage and the oil slick on my back doors/glass tomorrow. It drips faster than a woman crying while watching a Lifetime movie. When I pull in to Walmart (to buy more oil) in the rain, rainbow dots lead the way to my Tahoe like a Pac Man maze. Gretta Thunberg would put a hit out on my if she knew what a mess I was making. More pics to follow.
 

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