2023 Chevrolet Silverado 2500

While driving to work one day I came to an intersection and stopped. When I went to accelerate to take off my truck shuttered and made a loud noise. The truck immediately went into "Reduced Power Mode" with no warning. I could no longer drive the appropriate speed limit and had to constantly pull over to allow other vehicles to go by. This caused a traffic jam on narrow roads to get the vehicle to a safe spot. My truck only has 43,000 miles on it. The dealership confirmed that the truck has a bad valve body and needs to be replaced. The truck is currently sitting at the dealership and has been since May 15, 2025. As of today, July 18, 2025, GM still does not have an ETA on when the part to fix my truck will ship out.

I was on a two lane driving down the road and getting up to speed. I was still about 45 miles per hour on my way up to 55 mph my vehicle started de rating very fast as I’m driving and then my engine shut off. I had no control over my steering as I made a turn to get off the two-lane road because there was no shoulder. I had to turn the steering wheel really hard and was not able to control the vehicle at all because the engine shut down completely. Everything shut down. I was sticking out in the road. I have no clue yet. What caused it I had to get it towed to a dealership. I just thank God I wasn’t on an interstate but still I was on a two lane and had just topped over a small hill where nobody could see me when they topped the little hill. It could’ve been a very dangerous situation.

Sudden jerk power train and deceleration while driving and towing 5th wheel, immediate loss of power and could have been catastrophic. GM has a known defect that requires immediate attention and investigation to affirm this is a broad national problem with the Allison 10 speed 10L1000 transmission, specifically the defective transmission control valve body assembly. Do we have to wait for multiple family members to be killed or seriously injured due to this known defect? Time for action and resolution. My local dealer tells me this is bigger than anyone knows... why?

Component/System: The Allison 10‑speed (10L1000) transmission valve body catastrophically failed on [XXX], while driving Sunday afternoon down Galveston Seawall Blvd. The truck abruptly dropped from 45 mph into limp mode in heavy traffic, forcing me to pull into the bike lane to avoid being rear‑ended. The vehicle remains at Classic Chevrolet (Galveston, TX) awaiting the OEM valve body—which is on national backorder—and the complete transmission assembly is likewise unavailable. The failed valve body and transmission are available for inspection upon request. Safety Risk: Unexpected limp mode and gear lock‑up in heavy traffic create an immediate risk of rear‑end collisions or side impacts as surrounding drivers have no warning of sudden deceleration or loss of drive. Reproduction/Confirmation: Classic Chevrolet diagnosed and confirmed the failed valve body on May 12, 2025. Their service advisor and my assigned GM Case Agent (#[XXX]) have both acknowledged the defect but report no parts available for repair. Inspections: The vehicle has been inspected by Classic Chevrolet under warranty. GM Customer Care has reviewed my service orders and correspondence. No police or insurance inspections occurred, as no collision ensued—however, the roadside inspection at Classic Chevrolet confirmed the mechanical failure. Warnings/Symptoms: There were no prior warning lamps, messages, or symptoms before the failure. The valve body failure occurred without any advance indication. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Tailgate randomly opens and closes on its own. It will continue to do so until I start the truck up and then it will start doing it again as soon as I open my drivers side door. Also, the tailgate will no longer open by the button that is on the tailgate. The only way to open the tailgate is to push the button on the remote. And if you do that, the tailgate starts opening and closing again on its own.

My truck has 50k miles and while driving down the road heard a loud pop and felt the truck jerk. Then the truck entered low power mode and the engine light turned on. I took it to the dealership and they are contributing it to the transmission valve body. Has been in the shop for 3 week so far and still no update when the part will be available.