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

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Doubeleive

Wes
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the premium one, don't worry about the extra stuff you don't need this kit covers 99-14
proo1.JPG
 

Charlie207

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Replaced the valve cover gaskets, and cleaned up the schmoo from the valve covers.

oGETeO7.jpg

A3H45N2.jpg


Couldn't even start installing this clamp, because the ground strap bolt is King-Konged into the head. I guess I'll try to go up from below, but will have to remove the front drive-shaft.
qXYLYlN.jpg


I just noticed the 6.2 stamped under one of the valve covers. Is that because the 5.3 and 6.2 share the same heads?

Also, the Fel-Pro gasket set came with an extra gasket, and I have no idea where it is supposed to go. Looks like this:
rz9IFkE.jpg


Any clue?
 

Doubeleive

Wes
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Replaced the valve cover gaskets, and cleaned up the schmoo from the valve covers.

View attachment 401525
View attachment 401526

Couldn't even start installing this clamp, because the ground strap bolt is King-Konged into the head. I guess I'll try to go up from below, but will have to remove the front drive-shaft.
View attachment 401527

I just noticed the 6.2 stamped under one of the valve covers. Is that because the 5.3 and 6.2 share the same heads?

Also, the Fel-Pro gasket set came with an extra gasket, and I have no idea where it is supposed to go. Looks like this:
View attachment 401528

Any clue?
that gasket sets covers 99-20 could go to anything, off hand I would guess some form of pcv valve, it's not applicable for all.
 

ivin74

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Replaced the valve cover gaskets, and cleaned up the schmoo from the valve covers.

View attachment 401525
View attachment 401526

Couldn't even start installing this clamp, because the ground strap bolt is King-Konged into the head. I guess I'll try to go up from below, but will have to remove the front drive-shaft.
View attachment 401527

I just noticed the 6.2 stamped under one of the valve covers. Is that because the 5.3 and 6.2 share the same heads?

Also, the Fel-Pro gasket set came with an extra gasket, and I have no idea where it is supposed to go. Looks like this:
View attachment 401528

Any clue?
That gasket is for the old LS factory E.G.R. and A.I.R. connection if I'm not mistaken.
 

Doubeleive

Wes
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That gasket is for the old LS factory E.G.R. and A.I.R. connection if I'm not mistaken.
looks like a egr gasket, did you you have to pull the egr off to get the valve cover off on those? I can't remember on the old 350's I think you had to take the egr off to do the passenger side?
 

j91z28d1

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Cleaned the throttle body. Found the front two VLOM bolts loose. I snugged them up and put things back together. It doesn’t look to be too hard to take the intake off and retorque them. Just need to find a day to do it.


there's a theory that loose bolts are the cause of afm lifters sticking. it says being loose allows oil to leak internally on its way to the litter, over time the lack of lubrication inside the lifter, the plunger starts to gaul up and sticks. very tight tolerance in there.

no clue if it's true, but if you have active afm, probably worth tightening. if you don't have afm, eh they are always loose on every ls with any miles on them. my ls3 had some so loose you could take them out with your fingers at 100k. but eh, no afm so nothing to hurt.
 

j91z28d1

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Trying to get the ground strap bolt out of the back of the driver's side head. Not looking good, boys.


if I remember right, flex head gear wrench to get on it, and still had to use a pry bar against something for leverage to break it loose. amazing how gm will tighten a random ground torqued to within a mm of failure but volm cover, eh. snug at best.
 

j91z28d1

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very nice.. I really need to find the motivation to do everything you just did. got the stuff just not feeling it.

did you drain the block? I was looking and my software says you can unscrew a plug on each side and drain the block. I'd like to but that seems like a mess haha. 4wd stuff everywhere under there.

it is kinda crazy how much different my hose routing is from the standard trucks.
 

PG01

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very nice.. I really need to find the motivation to do everything you just did. got the stuff just not feeling it.

did you drain the block? I was looking and my software says you can unscrew a plug on each side and drain the block. I'd like to but that seems like a mess haha. 4wd stuff everywhere under there.

it is kinda crazy how much different my hose routing is from the standard trucks.
X2…..I’m getting lazy as I age
 

PG01

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Onlyone

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very nice.. I really need to find the motivation to do everything you just did. got the stuff just not feeling it.

did you drain the block? I was looking and my software says you can unscrew a plug on each side and drain the block. I'd like to but that seems like a mess haha. 4wd stuff everywhere under there.

it is kinda crazy how much different my hose routing is from the standard trucks.
No, I just pulled the hoses and let her drain. Took about 3 gallons. It wasn’t a true flush. More of a drain and fill. It had a new gm radiator at 100k miles and they flushed it then. The “old” fluid was like new clean.
 
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Onlyone

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Come over and do mine….. lol my is due for all the crap
Hell I’ve had this crap for weeks. I figured I better do it. After 50 this gets to be too much. I’m beat. I will say, you can go down a rabbit hole with this stuff. I had originally just bought the Ts. Then I was like, well while I’m at it……and on and on and on….
 

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