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

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Just Fishing

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If you have oil coming OUT of the passenger side, you have problems or are staying at WOT for far too long. I'd Y the valley pan PCV and the original driver side PCV together and run them to two catch cans in series.


Luckily, I'm not.
but when I had the Tahoe apart after trying the high-volume pump, I noticed some signs of oil on the throttle body
It was probably just because i had the intake on its end while i replaced the crank and rebuilt the transmission.
No other signs inside of the intake tube.

So, i did the second catch can as a test to be sure.
Even under WOT, I have no signs of oil coming out of there.

However, on the driver side I have oil.
Doesn't seem to matter of WOT or just normal driving.
Approx. the same amount of oil per time driven.
And I have the updated valve cover + a .75 valve cover spacer.

Still blaming those stupid lifters.
I'm hoping it helps once I finally have the insane amount of preload figured out.
I'm just dragging ass since i want to go outside and do things this summer. ;)


Those lifters were pretty much my only choice at the time when i ordered them... everything else was on back order.
What I wanted was ACDelco branded ones... :confused:


And I have been running the two catch cans in line with each other on the driver side valve cover.
Nothing is passing by the first can and getting caught in the second. :peace:


Thing that worries me is the carbon I saw on the pistons when I had the engine apart this last time.
Just making 100% sure it's not the fkn pcv.
 

RooTBeeRthe1st

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Not sure if something wigged out or what, but on the way home today, AC full blast, sitting at a light.
And then once the engine revs up goes back to 12.5 or higher.
Stopped at BevMo for some refreshments, started it back up and it was sitting at 14-14.3v for the 5 min drive home.
 

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CaptainAmerica1

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Good to know. Must have been a one year crossover?
I bought it used so I have now idea whether it started out with them or if some meathead added them. The truck was used as a tow vehicle for a small horse trailer. From what I gather it was not supposed to have them from the factory. All I can say is that I removed a set when I replaced the struts and shocks upon purchase.
 

Charlie207

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Got around to replacing my radiator, some hoses, and attempted to swap out all the transmission oil cool lines. But some issues popped up.

Had to trim the fan shroud due to the thicker core of this Champion radiator. No biggie, it went in fine, and I thought I was on a roll. Nope.

I can't figure out how to remove the the hardline that connects to the right side of the oil cooler (as you face the front of the grill) from the opening between the bumper and AC condenser.

I disconnected the lines from the transmission, and all clips and brackets, but no amount of twisting, rotating, or pushing would allow for the hardline to make it through the opening.

I ended up reinstalling the old lines because if I can get them out without cutting them, how do I get the new lines in?

Is there a trick for us 4x4 owners that I didn't notice in the videos I watched in preparation for this? The vehicles were either 4x2, or they never showed the removal of the lines.

To add to the fun, after getting everything new swapped in, and all hoses connected, I see coolant leaking out of the reservoir as I'm running the engine to burp the air out.

Wtf! I just replaced that reservoir less than six months ago. Trying to bum a ride from my neighbor to the parts store tomorrow morning to get a new one and finish this garbage.

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iamdub

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So, i did the second catch can as a test to be sure.
Even under WOT, I have no signs of oil coming out of there.

You'd have to do a lot of WOT/high RPM, like a road course and staying in 2nd-3rd gear the whole way to get oil flowing outta the passenger side.


However, on the driver side I have oil.
Doesn't seem to matter of WOT or just normal driving.
Approx. the same amount of oil per time driven.
And I have the updated valve cover + a .75 valve cover spacer.

Oil out the driver side is gonna happen. A lot of high RPM and/or WOT will increase the amount of oil. You're good.


Those lifters were pretty much my only choice at the time when i ordered them... everything else was on back order.
What I wanted was ACDelco branded ones... :confused:

I always wondered why, with all the trouble you've had with the fancy ones, you didn't just get OEM lifters.


And I have been running the two catch cans in line with each other on the driver side valve cover.
Nothing is passing by the first can and getting caught in the second. :peace:

Awesome! I should check the hose going to my intake from the catch can. If there's anything in it, I might get a second can. I have it down to the ounce at this point. I was short 4 ounces at the last oil change and drained 2 out of the can. I assumed the engine burnt the other 2. But, I recently discovered that my 1/4-turn drain valve on the catch can might be leaking. All this time, I thought my power steering hose was weeping. I think it's that valve dripping onto it. :confused:


Thing that worries me is the carbon I saw on the pistons when I had the engine apart this last time.
Just making 100% sure it's not the fkn pcv.

If the carbon was evenly balanced between all the pistons, it's likely just normal crud burnt outta the gasoline. PCV oil affects the rearmost cylinders.
 

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