Steve Macedo

All is good. It's amazing when you change a few words of what you find. Throttle body in the transmission. There is a service bulletin on this and found it on a different search. Changed throttle body, all fluids, filter and pan gasket/seals. All was accessible from the pan. Reprogramming of the TCM and so far so good. I was a bit scary to out of the blue to have the rear axles lock up. Really surprised a glad that Noone was close enough behind us and get rear ended. Thanks for checking

Thank you. I will continue to search. Going to take it in this morning to see if any codes come up.

My 2020 Chevy 3500 DRW locked up twice while towing my 5th trailer at 11,000. 58,000 miles on the truck with no issues to-date. While driving up a mountain highway at 50 mph. Rear wheels locked up and left 6-8 ft of skid marks. Truck then released and I was able to get it off the road. Crawled under and see nothing loose or leaking. Let the truck sit for probably 10 minutes running while checking. Slowly took off again and no issues at 45 mph and below. 2 miles down the road it happened again with same results. If I had to guess on the 10 speed transmission I would think 6 or 7 gear. Let it sit and again checking, nothing. Quick search of the web with nothing except torque converters. I received no check engine lights. Turned around and drove 45 mph and under back down the highway. No issues again. Made it home on country back roads. Had one steep pull out at 35 mph with no issues. We travel full-time and I baby this truck because I need it to last. Any thoughts

While pulling my 11,000 5th wheel trailer today. Going up an slight mountain highway incline at about 50mph. The truck came to a screeching halt. The rear axle left about a 6-8 ft skid mark from all 4 rear tires. As soon as the truck stopped, I was able to get pulled off to the side of the road. Thought we hit something. A look at the tires, driveline and any leaks maybe from the transmission. Nothing ? Drove about 2 miles up the road at about the same speed it happened again. The truck dash shows no check engine lights, did not flash anything at all. Parked the truck on a flat area and checked again. Nothing. Let the truck set for 30 minutes and then turned it around and headed back down the hill being super cautious. Made it home with no other issues and even had a steep pull out of a canyon at 35 mph. This is Friday at 4:30pm. No dealership in sight. Truck has 58,000 wirh no other issues. Transmission has NOT had its first service. Thoughts