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

[Rocket Man]

probably burnt a fuse (in the cluster) putting it in backwards, just figure which pin is positive and see if you can trace it. Does it start now with the cluster out? it should unless gm changed something from nbs to nnbs.

It starts. I opened the cluster and found only one fuse that’s labeled, surface mounted. It’s good. It probably shot voltage through pins that’s not meant for 12v. I’ll see when I get the cluster I ordered from LKQ if the problem is even in the cluster. The BCM isn’t throwing any codes other than it has no communication with the cluster.

 

[avalonandl]

probably burnt a fuse (in the cluster) putting it in backwards, just figure which pin is positive and see if you can trace it. Does it start now with the cluster out? it should unless gm changed something from nbs to nnbs.

Ooofta.,,.,

 

[iamdub]

I noticed it with the original sensors, I can't remember if I swapped those left to right or not, but when I put the brand new sensors in, it was still reading leaner on the driver side.

Ah. Then that sounds like it's not just a funky sensor, unfortunately. An exhaust leak would be obvious and I'm sure you would've noticed and mentioned one. So, check for an intake gasket leak.

 

[iamdub]

I was in a time crunch and took my brand new trans lines, cut the rubber portion away from the area the one goes up to the radiator as well as the one that goes out to the cooler. I carefully cut the metal clamps GM uses from the metal to the rubber part, it even has a flare on the metal, which is why I'm surprised I can't get the rubber to seal just using clamps. From there is where I just used rubber to the inlet/outlet of the cooler and onto the trans cooler lines. It was a temporary fix. I just don't know what sort of metal tubing to buy, like is it brake line, fuel line? I want to make my own metal lines going to the cooler and make it factory looking again with the snap in clips and all

I gotcha. You don't shop by the type of line, but by the size and material you want. It's definitely not brake line- way too big. If anything, it'd be classified as a fuel line. I'm pretty sure it's just regular 3/8" tubing, which you can buy in a bulk roll from many places.

Examples from Summit:

https://www.summitracing.com/search/part-type/tubing?N=tubing-outside-diameter:0-375-in

You have a caliper to measure it? A cheap digital caliper from Harbor Freight serves me just fine:

https://www.harborfreight.com/6-in-digital-caliper-63711.html

Another option, although costly but fancy, is to get tube-to-AN adapters and run AN to the cooler:

https://www.summitracing.com/parts/sum-2200077b


If you made your own lines, you'd have to splice them to the remains coming from the trans with unions. To reduce the number of splices/potential leaks, I'd just get new OEM lines for a model with the separate trans cooler and rotate that one leg around. You have to have a flex joint (the rubber portions) in there somewhere since the transmission and core support don't move in unison.

Here's a thread with pics of what I'm talking about. Yes, its a GMT800, but the same applies to the '900-


In this post, you can see how the factory setup is, then how the left side is rotated and the right side is moved over more to the driver side:

THE Tru-Cool 40K GVW Transmission Cooler Install Thread - PerformanceTrucks.net Forums

GM Drivetrain & Suspension - THE Tru-Cool 40K GVW Transmission Cooler Install Thread - I installed one of these way back in the day(2004) and since then get questions about it about once a week sometimes more. This last time around when I installed one I took a bunch of pictures and will be...

www.performancetrucks.net

This one shows the union and how the plastic was cut to facilitate the line being moved over to reach the cooler:

THE Tru-Cool 40K GVW Transmission Cooler Install Thread - PerformanceTrucks.net Forums

GM Drivetrain & Suspension - THE Tru-Cool 40K GVW Transmission Cooler Install Thread - I installed one of these way back in the day(2004) and since then get questions about it about once a week sometimes more. This last time around when I installed one I took a bunch of pictures and will be...

www.performancetrucks.net

 

[George B]

@mikeyss look for an Imperial or Rigid brand tube bender for bending 3/8” tube. Not many others work very well without buying a super expensive one.

 

[Just Fishing]

Started the hoe today, tried to get oil pressure by just cranking it but no go.

decided i better try and prime the pump..
Forgot to do that before i put the front axle in
couldn't get to the little port on the side of the block, nearly stripped it trying.

so i got the idea, pull the filter, and shove the tube from my priming tool up the pump side of the hole.
Pumped that b full of oil!

Finally got oil pressure.
lifters are taking forever to pump up, but that seems to be a thing with my LS7 lifters + the AFR springs in my heads.
Once they pump up i never have a problem afterwards (knock on wood!).


i don't have any accessory belts, and i sorta ran my battery down while doing the transmission re/de-tune.
Left hvac on while doing a "write entire"


And my balancer keeps sinking too far in each time i tighten down the bolt.
everything i read says that should seat against the timing gear?

I'm thinking my balancer is just wore out, probably over seated it the first time i did this with the 5.3.
So i found a "new old stock" balancer on ebay for $50
Ordered, crossing fingers!

If i still have the same problem, then i'm going to look at a spacer/washer of some sort.

 

[Just Fishing]

and since i really didn't find a solid cause of the issue.
I totally "cleansed" the hoe with sage.

I'm willing to try anything at this point.

 

[89Suburban]

Agree with Wes. Water doesn't travel uphill unless it has a siphon effect. There's no way enough would splash through there to see.

You don't think the front tire would sling it up? Or the car under wash jets? The lower part of the sill plate is bone dry so that is what's got me scratching my head.

 

[89Suburban]

Look at the moisture pattern on the bottom of this floor mat.

 

[89Suburban]

Red is bone dry, blue is wet.