2023 Chevrolet Silverado 2500

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.

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)

The contact owns a 2023 Chevrolet Silverado 2500. The contact stated that upon starting the vehicle, the check engine warning light illuminated. The contact restarted the vehicle, but the light failed to turn off. While driving 45 MPH hauling a trailer, the vehicle failed to operate as needed and the transmission was making an abnormal clunking sound. The vehicle then went into SAFE Mode and failed to exceed 35 MPH. The contact stated that the failure was related to NHTSA Campaign Number: 24V797000 (Power Train). The vehicle was taken to the local dealer, where it was diagnosed and determined that the valve body needed to be replaced. The vehicle was not repaired. The manufacturer was contacted and opened a claim for the contact. The failure mileage was approximately 29,000.

Vehicle was towing Horse Trailer. Gave an indication message to check trailer break wiring. I did so and all was working fine. I loaded my horses and pulled out onto the road. Traveling 10 mph the truck completely shut off, no brakes, No warning, I helplessly rolled to a stop. The truck then turned on electrically, but did not start the engine completely by itself. Two minutes later, the truck turned itself off electrically. The motor was never running. I had it towed to a dealership in which it took them five days to repair. The truck has 17,000 miles on it. If I would’ve been traveling on the expressway or going any faster, I could’ve killed people.. I personally have PTSD from ever driving this truck hooked to a trailer again. There should have been some kind of warning system. I should have never lost my brakes. I purchased this truck as a towing vehicle from my Horse Trailer And now I am terrified to use it!