Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2021 Chevrolet Silverado 2500 owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2021 Chevrolet Silverado 2500. The contact stated while driving 45 MPH and depressing the accelerator pedal, the vehicle failed to respond. There was no warning light illuminated. The contact was able to pull over to the side of the road and the vehicle was towed to the residence. The vehicle was then towed to the dealer, where it remained for two months, but was not diagnosed or repaired. The vehicle was then towed to John Elway Chevrolet (5200 S Broadway, Englewood, CO 80113), to be repaired under NHTSA Campaign Number: 24V797000(Power Train); however, after three months, the dealer informed the contact that the recall repair would not be honored because the emission system had been removed from the vehicle. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. …
The contact owns a 2021 Chevrolet Silverado 2500. The contact stated that while slowing down and coming to a stop, the accelerator pedal was depressed while in drive; however, the vehicle started to roll backwards. The contact depressed the brake pedal to prevent the vehicle from rolling backwards, and the RPM became elevated to 5,000 RPM. The contact immediately turned off the vehicle to prevent the RPM from continuing to increase. The vehicle was shifted to park, restarted, and then shifted to drive(D) and the brakes released. While releasing the brake pedal, the failure reoccurred. The vehicle was immediately turned off and towed to the residence. The dealer was informed of the failure of the clutch pack, which was welded together from friction. The dealer scheduled an appointment; however, the vehicle was not diagnosed or repaired. The manufacturer was not informed of the failure. …
The contact owns a 2021 Chevrolet Silverado 2500. The contact stated while driving at various speeds, the vehicle downshifted from 8th to 7th gear or from 8th to 6th gear, and the wheels locked up, causing the contact to lose control of the vehicle. There was no warning light illuminated. The contact was able to regain control of the vehicle and continued driving. The contact stated that the failure recurred several times while driving. The contact stated that the safety risk was more severe while towing a trailer because the failure caused the trailer to fishtail while driving. The contact stated that he had pulled to the side of the road on one occasion. The vehicle was taken to the dealer but was not diagnosed or repaired. The contact related the failure to TSB Number: 21-NA-275. The manufacturer was notified of the failure, but no assistance was provided. …
The contact owns a 2021 Chevrolet Silverado 2500. The contact stated while driving 55-60 MPH, the rear wheels seized. The contact had to release the accelerator pedal to self-correct the failure. The contact stated that the failure occurred twice. The vehicle was taken to the dealer, and the contact was informed that the vehicle was included in NHTSA Campaign Number: 24V797000 (Power Train); but was repaired. The contact stated while driving 25-30 MPH after the repair, the failure reoccurred a third time. The check engine warning light illuminated and the "Engine Power Reduced" message was displayed. The vehicle was taken to another dealer, Chevrolet of Montebello (310 W Whittier Blvd, Montebello, CA 90640); but was not diagnosed or repaired. The manufacturer was made aware of the failure and opened a case. The failure mileage was 122,000.
The contact owns a 2021 Chevrolet Silverado 2500. The contact stated that upon reaching his destination and shifting the vehicle into park, the vehicle failed to recognize that the gear shift lever had been moved to park (P). The contact stated that the "Please Shift to Park" message was displayed and the doors were unable to be locked. The vehicle returned to normal functionality, but the failure became a regular occurrence. No warning lights were illuminated. The vehicle was not taken to the dealer or an independent mechanic. The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was 25,000.
The contact owns a 2021 Chevrolet Silverado 2500. The contact stated while driving uphill at an undisclosed speed with a trailer hitched to the vehicle, the vehicle downshifted inadvertently, which caused the trailer to fishtail. The contact stated that he lost control of the vehicle, and he was able to slowly regain control of the vehicle. The contact stated that the failure had been recurring while driving. The vehicle was taken to an unknown dealer, where the cause of the failure could not be determined. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 110,000. The VIN was not available.
JULY 2022 DPF filter was throwing check engine light. Took to dealer to get diagnosed, part was ordered and the DPF was replaced August 19th 2022. Started to get headaches in vehicle while driving it. OCT 9th ended up in hospital after driving vehicle and was diagnosed with CARBON MONOXIDE POISONING. Experienced symptoms of losing consciousness, worst headache I've ever had, nausea for 5 hours, loss of feeling in body and seizing of body. Took truck to dealer to get inspected twice and nothing was found to be wrong with it. NOV 10th Took truck on another road trip and was having similar symptoms as before however had more chest pain this time so went back to hospital. Took truck back to dealer to have inspected again and was told that it was fine. Nov 18th took truck on another road trip and within 20 mins of driving had another horrible headache. …
2021, Chevrolet Silverado 2500 HD, Crew-Cab, 6.6L Gas Engine. At @ 25k miles, the "Service 4WD" light came on dash. It later started a grinding noise/sound within the front axle transfer case. Was told they had a problem with moisture intrusion into the transfer case and it would cause corrosion to sensor. Truck was taken to dealership and in shop for @ 1 week or so. After repair was completed, less than 3k miles later, it happened again. Same problem ("Service 4WD"), same noises, same diagnoses. Truck was taken back to the dealership. This time, repairs were more extensive and the wiring harness was replaced. I was traveling with work yesterday (34,458 miles on truck now) and the "Service 4WD" light came on again. I've contacted the dealership to schedule a time at the end of week or early Saturday to take the truck back again. …
GM has acknowledged the problem and has issued a recall on transmissions effecting 2020 - 2022 Chevrolet Silverado 2500/3500 Heavy Duty trucks equipped with diesel engines manufactured between January 28, 2019 - January 11, 2022. Our truck, a 2021 Chevrolet Silverado 2500HD, was taken in to D'arcy Chevrolet in Morris, IL to have Recall N242454440 - Momentary rear wheel lock-up - Transmission and Engine Control Module Programming with SP. Under this recall dealers will install new transmission control module software, free of charge. GM will provide a special coverage program to cover the repair of transmissions that are identified by the remedy software as containing a defective control valve. After the recall service was performed we were told by the dealership that the transmission needed to be replaced. …
first issue was around April-May 2025 when my engine started knocking and burning fuel. Warning light came on and it went right in to the dealer where I have all my maintenance done. They determined that it due to (2) faulty fuel injectors and I had them replaced at that time. In December of 2025 my engine started doing the same thing as before with the knocking and burning fuel and reduced speeds when on the highway so again it went into the dealer. It has since been in there and first was told it was the fuel injector again. They priced out the one was bad and I asked them to replace the remaining 6 fuel injectors so I didn't have this issue again in the near future. They did and the vehicle had the same issues going on. During the next inspection it was determined that the engine needed new rocker arms. …
Related recalls
Power train › Automatic transmission › Fluid/lubricant › Valves/valve body
General Motors, LLC (GM) is recalling certain 2020-2022 Chevrolet Silverado 1500, 2500, 3500, GMC Sierra 1500, 2500, 3500, 2021 Cadillac Escalade, Escalade ESV, Chevrolet Tahoe, Suburban, GMC Yukon, and Yukon XL vehicles equipped with diesel engines. The transmission control valve may fail and cause the rear wheels to lock-up.
Remedy: Dealers will install new transmission control module software, free of charge. GM will provide a special coverage program to cover the repair of transmissions that are identified by the remedy software as containing a…
Transmission complaints in other Silverado 2500 years
Frequently asked questions
How common are transmission problems on the 2021 Chevrolet Silverado 2500?
NHTSA has 30 complaints about the transmission & drivetrain of the 2021 Chevrolet Silverado 2500, 34% of the model year's 88 complaints.
Is there a recall for 2021 Chevrolet Silverado 2500 transmission problems?
Yes — NHTSA recall 24V-797 (valves/valve body, Oct 24, 2024). Recall repairs are free at authorized dealers.
At what mileage do 2021 Chevrolet Silverado 2500 transmission problems start?
Half of the complaints with a recorded mileage happened before about 100,000 miles.
Is it dangerous?
Owners linked 0 crashes, 0 fires and 1 injury to transmission & drivetrain problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.