What did you do to your NBS GMT800 Tahoe/Yukon Today?

[S33k3r]

That’s awesome that it’s getting a new paint job. Mine is sitting in the driveway waiting for me to find out if I blew the transmission again or I broke something else this time. Damn supercharger combined with the weight and AWD makes it really difficult to keep from breaking the drivetrain. Sigh. Waiting for spring because no shop. View attachment 451019

What transmission are you running?

 

[Rocket Man]

What transmission are you running?

Performabuilt Level 3 4L60 rated for 900 HP but with AWD and the weight combined with a blower and my right foot it’s been a problem. I’m nowhere near that kind of power. After the first 2 times I destroyed it they figured out I was screwing myself because I used RTV on the pan gasket both times I changed the fluid/ filter which blocked the servo passages so they weren’t releasing which caused it to shift REALLY firm, as in the whole truck would shake. The second time it twisted the output shaft in two, that was on a 1-2 shift. I thought we had it figured out and Ryan @ Performabuilt talked me out of upgrading to their Black Edition which they claim has never been broke. The parts were back ordered anyway. He rebuilt it that time for free even though it was a year out of warranty. This time I’m not sure what happened. I did do a short AWD burnout once or twice prior which is hard to do with the NVG149 transfer case it has. I actually haven’t even diagnosed it yet- maybe it’s not the trans but it seemed like it was; on a hard 3-2 downshift I heard something break and I drove a few more blocks to get off the expressway and when I pulled into a parking lot I had to manually downshift into first and then it just locked up and the engine died. It runs in neutral but as soon as I put it into gear it wants to die. I have to work on it in my driveway and I have been busy with health issues. I will figure it out and fix it. I have way too much time and money invested in this truck to give up although it crossed my mind. If it’s the transmission I have to ship it to the east coast from the west coast but I have done it twice already. I still have the shipping box.

 

[latvius]

Performabuilt Level 3 4L60 rated for 900 HP but with AWD and the weight combined with a blower and my right foot it’s been a problem. I’m nowhere near that kind of power. After the first 2 times I destroyed it they figured out I was screwing myself because I used RTV on the pan gasket both times I changed the fluid/ filter which blocked the servo passages so they weren’t releasing which caused it to shift REALLY firm, as in the whole truck would shake. The second time it twisted the output shaft in two, that was on a 1-2 shift. I thought we had it figured out and Ryan @ Performabuilt talked me out of upgrading to their Black Edition which they claim has never been broke. The parts were back ordered anyway. He rebuilt it that time for free even though it was a year out of warranty. This time I’m not sure what happened. I did do a short AWD burnout once or twice prior which is hard to do with the NVG149 transfer case it has. I actually haven’t even diagnosed it yet- maybe it’s not the trans but it seemed like it was; on a hard 3-2 downshift I heard something break and I drove a few more blocks to get off the expressway and when I pulled into a parking lot I had to manually downshift into first and then it just locked up and the engine died. It runs in neutral but as soon as I put it into gear it wants to die. I have to work on it in my driveway and I have been busy with health issues. I will figure it out and fix it. I have way too much time and money invested in this truck to give up although it crossed my mind. If it’s the transmission I have to ship it to the east coast from the west coast but I have done it twice already. I still have the shipping box.

Sounds like that company is really good, most of them won't do anything when it IS in warranty. Stick with it you're the only guy I know with a Denali that has a blower so very cool and unique!