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

[Onlyone]

Hell I even cleaned a few things up. Like 2 things lol
it was having a slight rough idle at cold start. Now it’s smooth and idles about 100 rpm higher is seems.

 

[j91z28d1]

man that thing is clean. white always look good when it's clean.

mine is black and looks like the last owner washed it with sand paper. I've been meaning to hit it with a buffer for 6 months haha.

I noticed mine ran noticeable smoother with new plugs too. I was surprised, they normally make any difference when I replace them in my cars. I didn't notice any higher idle thou.

 

[Rocket Man]

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….

You got plenty of years left to keep at it. I’m 63 and I still do my own work, it’s not that hard for me. The last time I pulled the trans was definitely hard though. That working on my back is for the birds.

 

[Doubeleive]

spotted this jalopy in the parking lot while doing my shipping, thought it had some kind of aftermarket bumper at first but then saw the "wilco" that's pretty crafty
I wonder what the ride quality is like, looked like he had some fox shocks with reservoirs up front didn't get them in the photo

 

[iamdub]

What is the consensus on intake gasket brand?

Fel-Pro or Mahle, IMO. I've never heard of the Fel-Pro metallized.

 

[Doubeleive]

Fel-Pro or Mahle, IMO. I've never heard of the Fel-Pro metallized.

They have plastic ones and metallized, the metal ones are better

 

[iamdub]

They have plastic ones and metallized, the metal ones are better

I looked 'em up after reading your post. What makes 'em better? The way I see it, all the frame does is hold it to the manifold, which, the plastic OEM style does perfectly fine. The gaskets are still the O-ring style in either the plastic or metal frame. I'm not arguing, just trying to learn what the reason is for the metal ones even being engineered. Like, is there a fault with the plastic frame design or...?

 

[Doubeleive]

I looked 'em up after reading your post. What makes 'em better? The way I see it, all the frame does is hold it to the manifold, which, the plastic OEM style does perfectly fine. The gaskets are still the O-ring style in either the plastic or metal frame. I'm not arguing, just trying to learn what the reason is for the metal ones even being engineered. Like, is there a fault with the plastic frame design or...?

years ago at a very reputable shop here in town the owner told me he sometimes had issue's with the plastic ones leaking and customers coming back and having to do warranty work, so he switched to the metal ones and had no problems, might be that the plastic ones warp or something I don't know that's the only thing I can come up with, i think he mentioned that the metal ones seemed to do better with the heat. I just took it for granted and have used the metal ones myself and have had no reportable issue's either. They are pretty nice (well made), cost a few bucks more but seem worth it.

 

[RooTBeeRthe1st]

Drove her up to my friends in Santa barbara, got her tent trailer out to fix a leaky air conditioner seal causing a bunch of roof damage.

 

[Charlie207]

Swapped in new radiator and water pump. No leaks so far......*

And, the loud noise was the water pump bearing, and it's gone now.

Now I can RMA that Champion all-aluminum unit.

Kinda surprised that one of the two new "8.8" bolts for the thermostat housing that came in the Gates water pump box stretched when being torqued to 11 lb./ft. I had to reuse the bolts that were there, but they did fine.

I wanted to also do an oil change and swap the pads/rotors, but after burping the coolant system the oil was too hot to play around with, so I went inside to cool down. This was three hours ago and I already cracked a barley pop, so I'll probably not get to that stuff today.

 

[me51]

They have plastic ones and metallized, the metal ones are better

Does this generation Small Block have the same issue as the old Vortec 5.7? (Intake Gasket leaks, coolant dripping into the crankcase mixing with oil)
I thought these were new enough to not leak there

 

[Doubeleive]

Does this generation Small Block have the same issue as the old Vortec 5.7? (Intake Gasket leaks, coolant dripping into the crankcase mixing with oil)
I thought these were new enough to not leak there

no

 

[Doubeleive]

the only reason generally to pull the intake on these is to do vlom work or maybe do the oil pressure sensor since it is in a rather difficult spot behind the intake but can be done without pulling the intake off

the gmt800's knock sensors are under the intake so it has to come off, on the gmt900's they are on the outside of the block

 

[Sparksalot]

Drove thecopcar a while today. I've notice a few random times the cruise wouldn't engage. Today it would drop out of cruise intermitantly. Tapping the brakes reset it, and away we go again. I'm guessing it's time for a brake switch change.

 

[Doubeleive]

Drove thecopcar a while today. I've notice a few random times the cruise wouldn't engage. Today it would drop out of cruise intermitantly. Tapping the brakes reset it, and away we go again. I'm guessing it's time for a brake switch change.

no codes for anything?

 

[Sparksalot]

no codes for anything?

Good point. I'll have to see if my scanner will read anything.

 

[Doubeleive]

Good point. I'll have to see if my scanner will read anything.

check the historical if nothing current as it could maybe point towards something

 

[Doubeleive]

historical codes can be a rabbit hole though if nothing looks related just ignore them mine has some that never go away and have always been there even if cleared out they magically re-appear and nothing is wrong with it.

 

[Sparksalot]

historical codes can be a rabbit hole though if nothing looks related just ignore them mine has some that never go away and have always been there even if cleared out they magically re-appear and nothing is wrong with it.

The only code it has.

 

[mikez71]

bypassed the ambient light sensor. Hooked up a 680 ohm and 10k ohm resistor to a relay harness. Triggered relay with trailer parking light fuse in fusebox. (the fused side, terminal furthest from cab) though im not sure if 18 gauge wire is enough to pop the stock 15A fuse, or if my wire would burn up with short) I might add a tap and put a smaller fuse in, though the wire is loomed up and in safe locations..

red wire (30 terminal) goes to the white wire in ambient light sensor (i de-pinned it and heat shrunk the wire on it in case it didnt work)
blue wire went to brown park lamp circuit (fusebox in my case)
all other wires are grounds, but two (87a and 87 terminals) with resistors soldered inline and a bunch of heat shrink to keep them from stressing the resistor leads.

no more dimming in the daytime, adjustable dimming at night.

UPDATE: One weird behavior.
When turning lights off, the dash display goes from nighttime dim, to off, then on daylight bright.
Does not cycle off when going from daytime to nighttime.
Not sure why, maybe the sudden change in voltage going from 10kohm resistance suddenly to 680ohm is too fast for the BCM to adjust?
That or some other electrical behavior I don't understand.. Any suggestions on how to wire a fix?

Reading up on something called a flyback diode.. something about voltage spikes when power to coil is cut, which would make sense why it happens turning lights off.
Ordered a relay with diode, but I'm not sure that's the issue.
also swapped my 85 and 86 (coil terminals) around. Sounds like conventionally 85 is -, and 86 is +.