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

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swathdiver

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Was shopping across the border in Detroit area, started smokin from coolant dropping onto exhaust.

Autozone was right on the corner and had new hose, so 10min later back on road.
That plastic design on these looks horrible
Not bad for sixteen years old. I just replaced mine in the 2009 as preventive maintenance and it was still in excellent condition.
 

iamdub

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I recorded a data log to update my transmission tune since the rebuild and torque converter replacement. I can't get enough of the sound of my built L9H. Procharger is very near in it's future now that the transmission is built. Here is a cell phone video:


Fun! I clocked right around 7 seconds 0-60, + or - a tenth or two. Stall looked to flash to 2500ish?
 

Charlie207

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Oil change, replaced the dumb chrome rear-view mirror covers with black ones, and got the car ready for a road-trip with two other couples this week by pulling out all the 2nd-row kid's booster seats, and throwing in a 3rd-row seat I just picked up.

Even drove through the car wash today, and vacuumed up all the Chex Mix and coins that had worked their way down between the kids seats.

Going to look at two 2nd-row captain's chairs after vacation.
 

pwtr02ss

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Hmmm. Are you on ios17?
IMG_6407.png
 

mikeyss

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I forgot that my Blackbear device still had older data logs from 2 years ago, so last weeks log file was only 3 mins long. I made a new log today, but couldn't resist making another full throttle video. This time I left traction control on, and surprisingly it seems a little quicker.

 
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I've never actually floored mine from a dead stop. I have gone about 3/4 throttle from a stop then rolled into it after getting going though. I'm always worried about breaking something since it weighs 6k lbs. Although it is AWD, so the power split is like 60 rear/40 front.

I have other vehicles I can drive if I feel the itch to launch hard and fast. Actually quite a bit faster than these pigs, lol
 

mikeyss

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I've never actually floored mine from a dead stop. I have gone about 3/4 throttle from a stop then rolled into it after getting going though. I'm always worried about breaking something since it weighs 6k lbs. Although it is AWD, so the power split is like 60 rear/40 front.

I have other vehicles I can drive if I feel the itch to launch hard and fast. Actually quite a bit faster than these pigs, lol
Maybe that is why my Tahoe came with the 14 bolt 9.5" rear differential, to help keep things from twisting up too much. Being in high altitude, (5k above sea level), I don't really worry about breaking anything when I floor it from a dead stop since I'm losing like 20% of my power. Plus, I don't really drive it hard too often, I've been doing this for logging purposes.

It is nice that you have other vehicles to drive when you have the itch to launch hard and fast, so do I. But I also like the sleeper affect my 'pig' has. My build isn't meant to be faster than mustangs or corvettes, it's my daily driver that was rare from the factory, and now has some extra goodies.
 

the_tool_man

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After fighting intermittent headlight issues with the aftermarket units I had (in my sig pic), I finally narrowed the issue down to a bad ground wire internal to one of them. Since I don't have the time or motivation to peel it apart today, I had to switch back to the faded, yellowed stock units. On the bright side I think stock headlights are less common than the aftermarket ones these days. I was getting tired of seeing so many Yukons with the same ones as me, lol. I'm not sure what I'm going to do. Choices seem to be stock, affordable crap that everyone else has, and HID retros at $1k.

20230930_144951.jpg
 

avalonandl

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After fighting intermittent headlight issues with the aftermarket units I had (in my sig pic), I finally narrowed the issue down to a bad ground wire internal to one of them. Since I don't have the time or motivation to peel it apart today, I had to switch back to the faded, yellowed stock units. On the bright side I think stock headlights are less common than the aftermarket ones these days. I was getting tired of seeing so many Yukons with the same ones as me, lol. I'm not sure what I'm going to do. Choices seem to be stock, affordable crap that everyone else has, and HID retros at $1k.

View attachment 410164
I have OE units with LED Sealights, work well. My RH HL has mositure in it.
 

the_tool_man

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I have OE units with LED Sealights, work well. My RH HL has mositure in it.
That's one good thing about the OEM ones. LEDs would fit. My aftermarket ones used H1 and H7 bulbs, which aren't as widely available in LED. I never did find any that even remotely fit without leaving them open in the back where water would get to them.
 

iamdub

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Maybe that is why my Tahoe came with the 14 bolt 9.5" rear differential, to help keep things from twisting up too much. Being in high altitude, (5k above sea level), I don't really worry about breaking anything when I floor it from a dead stop since I'm losing like 20% of my power. Plus, I don't really drive it hard too often, I've been doing this for logging purposes.

It is nice that you have other vehicles to drive when you have the itch to launch hard and fast, so do I. But I also like the sleeper affect my 'pig' has. My build isn't meant to be faster than mustangs or corvettes, it's my daily driver that was rare from the factory, and now has some extra goodies.

And it looks like you still have a lot of Torque Management left in the tune. Watching your vids is like watching mine with the noticeably slower RPM sweep until around 3,000 then it swings. I don't know the exact numbers, but even flooring it from a stop is about the same as going 75%. You're telling the PCM you want it all and it's gonna give you all it can, according to the tune. 100% commanded from the pedal doesn't equate to 100% throttle angle. Any further pedal travel is just reiterating to the PCM you want maximum launch but you're gonna get what it's programmed to give. Once moving, the 75% to 100% TA is more for determining the up shift. I'd say you're safe.

Running in our respective locations, you'd probably run .5 faster than me. If you came here, you'd drag my ass. Any plans to put it on the track?


 
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Maybe that is why my Tahoe came with the 14 bolt 9.5" rear differential, to help keep things from twisting up too much. Being in high altitude, (5k above sea level), I don't really worry about breaking anything when I floor it from a dead stop since I'm losing like 20% of my power. Plus, I don't really drive it hard too often, I've been doing this for logging purposes.

It is nice that you have other vehicles to drive when you have the itch to launch hard and fast, so do I. But I also like the sleeper affect my 'pig' has. My build isn't meant to be faster than mustangs or corvettes, it's my daily driver that was rare from the factory, and now has some extra goodies.
The RWD Denalis also have the 14 bolt 9.5" rear
 

mikeyss

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And it looks like you still have a lot of Torque Management left in the tune. Watching your vids is like watching mine with the noticeably slower RPM sweep until around 3,000 then it swings. I don't know the exact numbers, but even flooring it from a stop is about the same as going 75%. You're telling the PCM you want it all and it's gonna give you all it can, according to the tune. 100% commanded from the pedal doesn't equate to 100% throttle angle. Any further pedal travel is just reiterating to the PCM you want maximum launch but you're gonna get what it's programmed to give. Once moving, the 75% to 100% TA is more for determining the up shift. I'd say you're safe.

Running in our respective locations, you'd probably run .5 faster than me. If you came here, you'd drag my ass. Any plans to put it on the track?


I agree, I feel that there may be a lot of TM in my current tune. I am going to send my files to Blackbear this week, and now that my trans is new and built to handle at least 700 HP, maybe I'll be safe having the TM turned down. I also noticed when I'm driving at 50 and drop the hammer, it only downshifts to 3rd, not 2nd.
 

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