2023 CHEVROLET SILVERADO 2500 Power Train Problems

tramsmission valve body failed causing lack of porpulsion and inability to put the pickup in park while in traffic. after coasting to the nearest chevy dealer they cleared the codes so i could drive home and take it to my local chevy dealer asap. the local chevy dealer refused to inspect it until the check engine light came back. one week later the transmission violentley down shifted into 5th gear and stayed there until it was shut off it would not go into park. on the second occurances it gave codes p0700 and p0747. it was towed to the local chevy dealer who claimed to inspect on 3 ocassions but efused to give me any paper work on the results of the inspection. beacuse they never inspected it. i took it to an indepent mechanic to replace the valve body. the 5000 miles since the valve body replacement have been uneventful. no indicators of failure were seen before the inital failure.

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.

“Shift to Park” warning light appears even when vehicle is in park. Faulty solenoid in steering column.

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)

While driving my truck it shifts into tow mode by itself, also on june 1st 2025 my truck shifted to 4 low by itself .

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.

Truck has less than. 30k miles on it. Went into limp mode, was less than a mile from home. Parked it had it towed to nearest dealer. They then informed me they have 4 other truck sitting and waiting for Gm to fix parts with allison 10 speed transmission valve body. Dealer says it is at least 4 month wait to get my truck back. I work out of this truck for my business, and still have to pay my $1260 truck payment monthly for a truck that I can't use. Then they tell me they cant give me a loaner truck, only a car that i have to pay out of pocket daily for since chevy only covers $44 a day and cheapest rental is at $50 a day. I cant move trailers and equipment with a car. Gm knows there is a problem with these transmissions and won't do anything about it. I bought new thinking I'd be doing okay with extra warranty, but here we are with no real solution. Please help!!!

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.

Mileage: 29,000

Traveling 70mph on parkway, out of nowhere, the RPM start revving like the transmission had shifted into neutral, but it is still in Drive. Managed to get off at next exit allowing the Truck to coast. At stop sign, the Truck slams into first, slams into second, reaches 30mph and begins to do same problem and RPM’s rev like in neutral. Can not get the truck to go over 30mph of change any more gears. We did manage to take a 15 min ride to nearby Chevy Dealer. Dealer has confirmed no codes or check engine lights. After 1 full week in, no further information has been provided except at some point next week, it’s on the schedule to open the transmission. Vehicle is now stuck in Maryland. I did receive a rental to continue my way home that evening to SC.

When slowing down the vehicle and almost coming to complete stop the truck shutters when it shifts down. Also, if slowing down and almost coming to a stop and then accelerating the truck hesitates, and then shifts hard. The truck hesitating has caused a delay in clearing traffic while turning to exit the road.