What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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992dr

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Oil pressure relief valve is inside the oil pan and pops open when AFM engages. The oil sprays inside the pan and not anywhere outside. Well, I guess you could consider the one in the oil pump a relief valve as well. Regardless, if either of these are causing an EXTERNAL oil leak, then you have some serious problems!




It's kinda difficult to see, but grab a bright flashlight and a small flathead screwdriver. Pry out the round hole plug (inspection cover) and shine the light up in there. Aim it between the flexplate and engine block. Look for oil trails coming from up near the crank.

Here's an interweb pic of the flexplate as seen through the hole with the cover removed:

aac19d21a127dafb27e72f31852ce3b2.jpg

I think I'm thinking of something different that's on the back top of the block that is prone to leaking. Maybe that's for the Gen III though.

Ahhhh yes I will do that. I completely forgot about that access port or whatever you call it. I'll get under there this weekend and see what's going on. It would be obvious if it were leaking from there.
Everything is on the interwebs nowadays haha

Thanks man
 

iamdub

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I think I'm thinking of something different that's on the back top of the block that is prone to leaking. Maybe that's for the Gen III though.

Ahhhh yes I will do that. I completely forgot about that access port or whatever you call it. I'll get under there this weekend and see what's going on. It would be obvious if it were leaking from there.
Everything is on the interwebs nowadays haha

Thanks man

Oh, yeah! The oil pressure sensor! That's on the top rear of the block on the Gen4 as well and, yes, it is a common leak point. The Gen3 also has the cam sensor there that can seep oil as well.
 

992dr

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Oh, yeah! The oil pressure sensor! That's on the top rear of the block on the Gen4 as well and, yes, it is a common leak point. The Gen3 also has the cam sensor there that can seep oil as well.

Haha that's what I was thinking, oil pressure sensor. I'll have to pull out the telescoping mirror this weekend to.
 

Drok

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Ive never had good luck with plasti dip. I had it on my 05s grill amd after a month it started to fade and start to turn brownish.


Still look good that color though...
 

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