tiwillia

I've just learned to ignore it. It stopped appearing daily and now appears maybe once a week. If it gets bad again I'll take some time to check all my grounds and do some more troubleshooting.

Thanks for the follow-up!

Any updates on this? I'm seeing the same nearly daily now, running through the testing here and the voltage drops look good, boot in the door is dry. Thinking its my window motor as well since my drivers window moves up/down slower than the rest of the windows. Were you seeing the same prior to the window motor replacement?

Thanks for all the info - the torque converter not locking in reverse makes a lot of sense, it definitely never felt like it locked even when getting up to 5+ mph. I'll be scheduling another ~$300 transmission flush with the dealer today. Wish I didn't have to use the dealer.

The flush was done by the dealership. They used the new Mobil1 fluid that GM recommends after the TSB on the 8speed came out. The filter was not changed, they explained to me that it was a reverse flush that should clean the filter, so there wouldn't be a need to change it.

I think you're right, in hindsight it would have made more sense to idle the truck. I was just shocked that it had reached that temperature and probably didn't think it through. Thanks for your input.

2017 GMC Sierra Denali 4x4 6.2, 8-speed auto, 51.5k miles I was hauling a trailer full of maple hard wood here in the Appalachians, probably ~3500lbs. I had to reverse the trailer up a long (1/4 mile), steep (13 degrees according to the 4x4 info screen) driveway to get it to where it needed to be unloaded. About 95% of the way up the hill I noticed a burning smell. I continued since I was on the steepest part and just about at the top. Once I parked, I look at the trans temp guage and its just under 300F. I shut off the truck immediately and let it cool down to ~210F while unloading before driving the truck back down the mountain. There were no leaks that I can see. The truck drove home with the empty trailer as normal without any issues. I had a transmission flush about 500 miles ago prior to this @ 51k miles, so it has brand new transmission fluid in it. Looking for opinions on two questions: What would you do next? Ignore it? Get the transmission drail & filled? Get the transmission flushed again? Is there any way short of dropping the transmission pan to check the color/smell of the fluid? What should I check besides visually verifying there were no external leaks?

Totally guess-timating here so this isn't an actual quote, I'd have to weigh and measure these after packaging them up, but it looks like it would be $250-350 to ship through ShipNex, supposedly the cheapest way to ship tires/wheels:

I'll consider shipping on buyer's dime. It will be expensive for sure, these things are heavy.

4 2017 GMC Sierra Denali take-offs with General Grabber APT All-terrain tires. Tires have ~10k miles on them, plenty of tread left as can be seen in the pictures. These tires are fantastic, I miss them already, they are surprisingly quiet for how aggressive they are. Diameter: 22" Width: 9" Offset: 31mm Backspacing: 6.22" Tire size: 285/45/22 TPMS Sensors: Not included, swap your own in. Lug Nuts: Included One of the wheels was bent on the back-side on a pothole a couple months ago. It was professionally repaired by Real Wheel in Black Mountain (would highly recommend them). I've since put ~500 miles on the wheel/tire without any issue. Repair is even difficult to spot unless you know where it happened on the rim. Normal amount of wheel weights on the Rim. $1,400 OBO Willing to meet within ~100 miles of Asheville, NC or can meet in Raleigh, NC.

Thanks for the pictures here - they convinced me to make the switch after bending one of the stock Denali 22" wheels on a pothole. No more having to feel like the truck is fragile. Honestly rides better with more air between the truck and the road. Here are some pics: