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

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j91z28d1

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well....oil leak still happening. guess its either rear main or oil pan gasket. damn it.

ls oil pan gaskets all leak like clock work it seems. it's a damn shame gm used all rubber and o'ring style gaskets but speced them to leak around the same milage as old cork gaskets on a Gen one small block chevy. once they went to rubber on those they didn't even leak much.


I honestly have never figured out how gm did such a good job designing the ls and such a bad job sourcing quality parts. any run of the mill cheap felpro oil pan gasket is atleast made if oil resistant rubber.


it's very annoying.
 

Geoffsfas10

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ls oil pan gaskets all leak like clock work it seems. it's a damn shame gm used all rubber and o'ring style gaskets but speced them to leak around the same milage as old cork gaskets on a Gen one small block chevy. once they went to rubber on those they didn't even leak much.


I honestly have never figured out how gm did such a good job designing the ls and such a bad job sourcing quality parts. any run of the mill cheap felpro oil pan gasket is atleast made if oil resistant rubber.


it's very annoying.
im inclined to think this is the pan gasket, if i pull the inspection cover on the bellhousing, its all dry up on that back side. but the block is wet around the mating surface of the pan. its also a very slow leak, and doesnt leak when its parked up. if i wipe it all clean, and dont drive it for a few days, it stays dry
 

89Suburban

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im inclined to think this is the pan gasket, if i pull the inspection cover on the bellhousing, its all dry up on that back side. but the block is wet around the mating surface of the pan. its also a very slow leak, and doesnt leak when its parked up. if i wipe it all clean, and dont drive it for a few days, it stays dry
Don’t forget besides just a rear main seal there is the cover gasket that it is mounted in that can also start to fail and leak. Either can most certainly leak and it still look bone dry inside that inspection cover.
 

Doubeleive

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im inclined to think this is the pan gasket, if i pull the inspection cover on the bellhousing, its all dry up on that back side. but the block is wet around the mating surface of the pan. its also a very slow leak, and doesnt leak when its parked up. if i wipe it all clean, and dont drive it for a few days, it stays dry
take a look at the dip stick tube also where it goes in on the right side, it has a o-ring and believe the crank position sensor has a o-ring as well, sort of behind the starter.
 

Doubeleive

Wes
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bummed about my leak too! Have to look some more as well...

Got new rear calipers today.. last set at rockauto..
acdelco, supposed to be heavier duty with silicone seals..
View attachment 448667

Bought some crush washers too, but they came with some wider ones anyway..
View attachment 448668
I bought the same heavy duty black ones for the front, so far they have been holding up well to my abuse about 3 years now. Went thru 2 sets before them one leaked and one was sticky. they were $207 for the pair, now they are $313.99 :mad: thanks Joe
 

mikez71

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These were $243 for the pair, almost $100 more for the set compared to standard delco gold ones.
They look the same but without coating, different seals, pressure testing and hi-temp lube.

I see them on rockauto again, so I guess they got more in stock..

Glad to hear your's have been holding up, but sad to hear your old ones were not!
 

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These were $243 for the pair, almost $100 more for the set compared to standard delco gold ones.
They look the same but without coating, different seals, pressure testing and hi-temp lube.

I see them on rockauto again, so I guess they got more in stock..

Glad to hear your's have been holding up, but sad to hear your old ones were not!
I am pretty rough on brakes more than almost anyone, I have warmed these up pretty good a few times and there still good to go
one of these days I am going to figure out how to make some air vents like these work, just need some "free" time
maybe feed the air in from around the tow hooks or something
vents.JPG
 

j91z28d1

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I used sub ports when I built mine. not in the yukon but other car. they look nice in a flat surface, come in different sizes. I couldn't run 3in all the way like race car stuff, 2.5in fit nicely and they have a grid to block leaves and trash for street/highway driving.

worked pretty good. still over heated the pads in track but took a few laps longer. I need to bit the bullet and go with straight race pads and just swap them at the track. high temp street pads couldn't handle it.

Img_2025_01_26_09_04_52.jpegImg_2025_01_26_09_05_01.jpeg
 

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