General Motors LLC (GM) is recalling certain 2019 Chevrolet Silverado 4500, 5500 and 6500 vehicles and 2017-2019 Chevrolet Silverado 2500 and 3500 vehicles and GMC Sierra 2500 and 3500 vehicles equipped with Duramax 6.6 liter diesel engines and an optional...
Engine & cooling
GMC Sierra 2500 Engine problems by year
43 complaints filed with NHTSA about the GMC Sierra 2500's engine & cooling. Stalling, loss of power, oil consumption, overheating, head gaskets, timing chains and engine failure.
Engine complaints by model year
Engine recalls
Latest Sierra 2500 engine complaints
On 07/10/2026 at approximately 1:10 a.m., the parked and unoccupied vehicle caught fire while turned off. The vehicle had not been driven for several hours. A neighbor was awakened by the horn/alarm and popping noises, observed fire near the passenger-side cab/engine area, and called 911. The fire rapidly spread throughout the cab, engine compartment, rocker-panel areas, wheel wells, and truck bed, creating an explosion hazard and threatening a nearby occupied residence and garage. The fire department extinguished...
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the blaze, but the vehicle was completely destroyed. Before the fire, the vehicle had experienced recurring coolant warnings, a DEF-system warning, and delayed starting associated with the main battery. No smoke, fuel odor, intentional ignition source, charging device, or known external fire source was present before the incident. Weather was calm. The exact failed component and cause remain UNKNOWN. A firefighter stated that the apparent fire origin was near the passenger side of the vehicle. The remains are available for inspection, subject to coordination with the vehicle owner and insurer. The incident has been reported to the fire department, insurer, manufacturer, and NHTSA.
The contact owns a 2020 GMC Sierra 2500. The contact stated that the check engine warning light was illuminated, and the message "Reduced Power" was displayed. The vehicle was taken to the dealer, where the turbo actuator and wastegate position sensor A-circuit were replaced; however, the failure persisted. The vehicle was taken back to the dealer, and the contact was advised that another diagnostic test was needed. The contact declined to pay for the diagnostic test. The vehicle was taken to a retired GM mechanic,...
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who diagnosed the vehicle with turbo charger failure. The vehicle was not repaired due to the cost. The manufacturer was notified of the failure, but no assistance was provided. The failure mileage was approximately 100,000.
I am reporting repeated failures involving both the transmission and diesel emissions (DEF) system on my 2021 GMC Sierra 2500HD Denali equipped with the 6.6L Duramax diesel engine and Allison 10-speed automatic transmission. While under warranty, the truck required replacement of the aftertreatment fuel injector and later the Reductant Control Module due to DEF/emissions system failures. General Motors also completed recall-related transmission software updates on the vehicle. At approximately 154,833 miles, the...
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transmission began shifting improperly, set transmission fault codes, and required complete replacement at my expense. Less than 5,000 miles later, the vehicle again experienced a "Service DEF System" warning with multiple diagnostic trouble codes. Repairs required replacement of the DEF tank, DEF heater assembly, and NOx sensor. These repeated failures involve major drivetrain and emissions components on a heavy-duty truck. DEF system failures can place the vehicle into reduced-power (derate) mode, limiting vehicle performance and creating potential safety concerns while driving or towing. I am submitting this complaint so these failures can be documented as part of NHTSA's evaluation of similar vehicles.
The contact owns a 2021 GMC Sierra 2500. The contact stated that while driving at 55 MPH, the vehicle stalled unexpectedly. There were no warning lights illuminated. The vehicle was taken to the local dealer, where it was diagnosed, and determined that the engine needed to be replaced. The engine was replaced; however, the failure recurred. While at a stop and attempting to drive around a curve, the vehicle stalled. No warning lights were illuminated. The vehicle was taken to the local dealer, where it was diagnosed with engine failure. The vehicle was not repaired. The failure mileage was approximately 77,000. The VIN was not available.
80,000 Miles, complete engine break down. 12,000 to repair
Catastrophic engine failure after taking it in for the April 2025 recall. Complete engine replacement needed
The catalytic converter failed at 93,000 miles, and 64 months. GM says it is out of warranty.
Emissions Code showed up on the dash display. Tried to fix the fuel filter and cleaned a sensor off and it still shows the emissions code.
I rely heavily on this vehicle for my business and within 1 year of ownership, the vehicle broke down on the highway allowing it to only run @ 30mph. After finally locating a dealer who could evaluate the vehicle in less than 1 week, I was informed that the part was unavailable and they indicated, "it could take 1 month or 3 months to receive." Following multiple conversations, I was forced to open a claim with GM Customer Care. While trying to get information, I was, at one point, told that "although the code...
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indicates failed transmission control module, it doesn't happen all the time and if I wanted to drive it I could come and take it until the part arrives." That really told me alot about how GM representatives view SAFETY while when it happened, I was on Interstate and nearly got trounced by oncoming heavy traffic while pulling an equipment trailer. After the case was handed off to several GM Customer Care Representatives, I finally rec'd feedback including several email updates. I finally rec'd the vehicle back after 1 month and was informed that 1) would receive car payment from GM & 2) would receive additional compensation for lost work time while my vehicle was out of service (Jan 2024). Since that conversation, I did receive 1 car payment however, never heard back from Alisa regarding "lost time". I have sent several emails to customer care asking for an update however, crickets. Furthermore, the car has returned to the shop for another warning to "shift vehicle to park" when it was in park. They told me its a electrical malfunction but they could not get the error to come up on test. I have a photo showing the error.
The contact owns a 2020 GMC Sierra 2500. The contact stated that the vehicle was under NHTSA Campaign Number: 24V797000 (Power Train) and the vehicle was repaired. The contact stated that after the recall repair, the transmission started shifting hard. The vehicle was taken to the dealer, and the contact was informed that the transmission module would reprogram and adjust independently. The contact stated that a week later, while driving approximately 45 MPH, the vehicle started to run rough, and the message engine...
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power reduced was displayed. The transmission fault, parking brake system alert, service parking brake, and the check engine warning light illuminated. The vehicle was towed to the dealer, who diagnosed the vehicle and determined that the fuel injector was open, causing high resistance in the connector for cylinder #4. The transmission could not be diagnosed until the injector was repaired. The manufacturer was informed of the failure and opened a case. The failure mileage was 125,000.
The contact owns a 2020 GMC Sierra 2500. The contact stated while driving at an undisclosed speed, the accelerator pedal was depressed, and the transmission jerked. The contact stated that the transmission was skipping gear while shifting. The check engine warning light turned on and off. The contact received notification of NHTSA Campaign Number: 24V797000 (Power Train); however, the part to do the recall repair was not yet available. The local dealer was contacted. The contact stated that the manufacturer had...
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exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The failure mileage was approximately 114,000. VIN tool confirms parts not available.
The contact owns a 2021 GMC Sierra 2500. The contact stated while driving 40-55 MPH, the vehicle started losing motive power. The contact stated while pulling into a nearby independent mechanic shop, the vehicle started jerking significantly and stalled midway. The check engine warning light was illuminated. The mechanic diagnosed the vehicle with transmission failure. The vehicle was towed to the residence. The local dealer and several unknown dealers were notified of the failure and informed the contact that the...
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transmission assembly was not available and could not be ordered. The vehicle was towed to CJ's Transmission, where the transmission was taken apart. The mechanic determined that the transmission needed to be replaced. The vehicle was being repaired with a rebuilt transmission. The contact received notification of NHTSA Campaign Number: 24V797000 (Power Train); however, the part to do the recall repair was not yet available. The local dealer was contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the failure and offered a modest monetary compensation for the repair. The failure mileage was approximately 134,000. Parts distribution disconnect.
I was driving on the interstate and had just exited to refuel. As I was re-entering traffic, I accelerated to merge, and suddenly, as I was about to pull in, I felt and heard a massive metallic crash, like the entire transmission had dropped. The engine sounded abnormal, and immediately, the dashboard flashed a warning: 'Engine Power is Reduced.' The check engine light came on, and I got messages saying the transmission needed service and to schedule an appointment. I called my dealership and took it in as soon as...
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possible. After they held the truck for a while, the service manager told me a critical part was on indefinite backorder with no fulfillment date. He handed back my keys, saying they'd reach out when it arrived. I asked if it was safe to drive, and he said yes. Later, driving from Illinois to California, my truck malfunctioned again. This time, in heavy, 12-lane traffic, the same loud crash threw me forward, almost slamming my face into the steering wheel. My wrists and shoulders hurt from bracing myself, and my right shoulder still aches. Again, I got the 'Engine Power Reduced' warning and transmission service notice. Each time, this has put me and those around me in severe danger.
Defective valve body We took in our vehicle for issues with the engine. We were not able to drive it over 50 mph it only has 22,000 miles. The dealership has had the vehicle since August 13th. They have had the vehicle for 9 weeks. They said that neither them or customer [[redacted]] (CASE # [[redacted]]). Can locate a valve body, to replace the defective one. We were made aware that we had an issue when our check engine light came on. We proceeded to have a diagnostic done thru on-star. Then immediately took it to the dealership for repair. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
The contact owns a 2019 GMC Sierra 2500. The contact stated while driving at various speeds, the vehicle lost motive power. The coolant fan seized and failed to operate as needed. There were no warning lights illuminated. The vehicle was towed to the local dealer to be diagnosed. The contact was informed that the check engine warning light was illuminated, and the knock sensor, coolant fan clutch, injector #6, and unstated wiring harness needed to be replaced. The dealer informed the contact that the parts to...
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repair the vehicle were on back order. The vehicle was not repaired. The manufacturer was contacted and opened a case, but no additional assistance was provided. The failure mileage was approximately 87,000.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) complaints and recalls, checked daily. Complaints are owners' own reports and are not verified. How we use the data