2021 GMC Sierra 1500
Problems, recalls and owner-reported issues
Engine is the leading concern among 572 owner complaints filed for this model year. This is the 5th highest complaint count among 26 Sierra 1500 model years with reports.
Of the 2021 reports, 5 involved a crash and 6 involved a fire. 2 people were injured.
What owners report most often
Recalls and investigations
Power train, automatic transmission, control module, softwareFeb 12, 2026
General Motors, LLC is recalling certain 2020 Chevrolet Silverado 2500, 3500, GMC Sierra 2500, 3500, and 2020-2022 Chevrolet Silverado 1500 and GMC Sierra 1500 vehicles that may have been repaired incorrectly under recall 24V797. The transmission control valve may fail and cause the rear wheels to lock up.
Rear wheel lock up increases the risk of a crash.
Dealers will inspect the vehicles and update the transmission control software, free of charge. Owner notification letters were mailed March 6, 2026. Owners may contact GMC customer service at 1-800-462-8782 or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N252516560. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov on February 12, 2026.
Campaign 26V083000 on NHTSA.gov
Engine and engine cooling, engine, hard parts internal/mechanicalApr 24, 2025
General Motors LLC (GM) is recalling certain 2021-2024 Cadillac Escalade and Escalade ESV, Chevrolet Silverado 1500, Suburban, and Tahoe, GMC Sierra 1500, Yukon, and Yukon XL vehicles equipped with a 6.2L V8 gas engine. The connecting rod and/or crankshaft engine components may have manufacturing defects that can lead to engine damage and engine failure.
Engine failure increases the risk of a crash.
Dealers will inspect the engine, and as necessary, repair or replace the engine. For vehicles that pass inspection, dealers will add higher viscosity oil, install 6 oil fill cap, replace the oil filter, and update the owner's manual. Repairs will be performed free of charge. Owner notification letters were mailed June 18, 2025. Owners may contact Cadillac customer service at 1-800-333-4223, Chevrolet customer service at 1-800-222-1020, or GMC customer service at 1-800-462-8782. GM's number for this recall is N252494000.
Campaign 25V274000 on NHTSA.gov
Power train, automatic transmission, control module, softwareOct 24, 2024
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.
Rear wheel lock-up can increase the risk of a crash.
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. Owner notification letters were mailed December 12, 2024. Owners may contact GM customer service at 1-888-988-7267, Cadillac customer service at 1-800-458-8006, GMC customer service at GMC 1-800-462-8782 or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N242454440.
Campaign 24V797000 on NHTSA.gov
Tires, temporary/emergency spare tireDec 16, 2021
General Motors (GM) is recalling certain 2019-2021 GMC Sierra 1500 and Silverado 1500 vehicles equipped with certain accessory road tires and a 17" spare tire. The 17" spare tire provided with the vehicle is not compatible for use with the accessory wheels, which can cause the anti-lock brake system (ABS) to not function properly under certain conditions.
An ABS system that does not function properly can increase the risk of a crash.
Dealers will provide a new 17" spare tire and wheel assembly that is compatible with the accessory wheels, free of charge. Dealers will also apply a new spare tire information label, and provide owners with an owner's manual insert clarifying which spare tire to use with the accessory road tires and with the 17" original tires. Owner notification letters were mailed February 7, 2022. Owners may contact GM customer service at 1-800-462-8782 or GMC customer service at 1-800-462-8782. GM's number for this recall is N212346510.
Campaign 21V985000 on NHTSA.gov
Seat beltsDec 23, 2020
General Motors, LLC (GM) is recalling certain 2020 Chevrolet Bolt EV and 2021 GMC Canyon and Sierra 1500, 2500 and 3500, Yukon, Yukon XL, Cadillac Escalade and Escalade ESV and Chevrolet Blazer, Camaro, Colorado, Equinox, Silverado 1500, 2500 and 3500, Suburban and Tahoe vehicles. Incorrect bolts may have been used at one or more fastening locations to secure the seat belts to the vehicle. If an incorrect bolt was used, the seat belt may not be properly attached to the vehicle.
If a seat belt assembly is not properly attached to the vehicle, the seat belt may not properly restrain an occupant in the event of a crash, increasing the risk of injury.
GM will notify owners, and dealers will replace the suspect bolts, free of charge. The recall began January 29, 2021. Owners may contact GMC customer service at 1-800-462-8785, Cadillac customer service at 1-800-458-8006, or Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N202322230.
Campaign 20V811000 on NHTSA.gov
Seat beltsDec 17, 2020
General Motors, LLC (GM) is recalling certain 2019-2021 Chevrolet Silverado 1500 and GMC Sierra 1500, 2021 Chevrolet Suburban and Tahoe and GMC Yukon XL and 2020-2021 Chevrolet Silverado 2500 and 3500 and GMC Sierra 2500 and 3500 vehicles. The seat belt brackets may not be secured to the seat frame in the front-row center seating position.
If a seat-belt bracket is not secured, the seat belt may not properly restrain an occupant in the front-row center seat position, increasing the risk of injury in a crash.
GM will notify owners, and dealers will inspect left-side and right-side front-row center seat-belt bracket attachments and reassemble it correctly as necessary, free of charge. The recall began January 26, 2021. Owners may contact GMC customer service at 1-800-462-8782, Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N202314670.
Campaign 20V792000 on NHTSA.gov
TiresNov 5, 2020
General Motors LLC (GM) is recalling certain 2020 Buick Enclave, Cadillac XT5, GMC Acadia and Chevrolet Traverse vehicles and 2020-2021 Chevrolet Silverado 1500, GMC Sierra 1500 vehicles. The vehicles may have been manufactured with Continental tires that were overcured.
Overcured tires may experience a carcass break in the sidewall resulting in a sudden air loss or could develop a belt edge separation which could lead to partial or full tread/belt loss. Either condition increases the risk of a crash.
GM will notify owners, and dealers will inspect vehicles and replace tires that have DOT number and production mold number combinations identified by Continental, free of charge. The recall began December 17, 2020. Owners may contact GMC customer service at 1-888-988-7267, Buick customer service at 1-866-608-8080, Chevrolet customer service at 1-800-222-1020 or Cadillac customer service at 1-800-458-8006. GM's number for this recall is N202319030.
Campaign 20V684000 on NHTSA.gov
Representative owner complaints
572 reports, newest first.
Structure, May 4, 2026
The contact owns a 2021 GMC Sierra LD Crew. The contact stated that while driving on the highway at an undisclosed speed, the vehicle's bedrail attachment fully detached from the vehicle. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was unavailable.
Engine, May 2, 2026
Engine coolant control valve needed to be replaced. Special coverage (N252508341) was issued out by GM to fix this problem on 2021 GMC Sierra 1500 vehicles.
Engine, Apr 29, 2026
Driving normal traffic . Started hearing ticking . Check engine light flashing ,service esc and braking system light up. Parking not loud ticking from engine bay
Steering, Electrical system, Apr 24, 2026
Driving down road and had total loss of power steering and yes it is available for inspection. Almost drove it off the road due to loss of steering Yes, it happened to be a failed main grounding strap that created the issue. The dealership made the repair. No, it was inspected and repaired by the dealership Yes, started with loss of power steering, then truck died and these codes popped up: Low fuel code, but tank was full; trailer brake system code; side detection code and esc traction control code.
Suspension, Service brakes, Hydraulic, Apr 23, 2026
The contact owns a 2021 GMC Sierra 1500. The contact stated that while her son was driving 55 MPH and depressing the brake pedal, the vehicle failed to slow down as intended. The driver attempted to use the parking brake to slow the vehicle, but the vehicle failed to slow down. The message “Braking System Failure” was displayed. The driver pulled over to the side of the road, and the passenger’s side front wheel detached and started leaning to the right before the vehicle came to a stop. The driver exited to inspect the vehicle and became aware that the front passenger’s side wheel was lying on the ground. The vehicle was towed to an independent mechanic, but was not diagnosed. The vehicle was then towed to another dealer, where it was diagnosed, and it was determined that the passenger’s side upper and lower control arms, ball joints, rack and pinion, brake rotor and pads, hub, outer tie rod, brake line, speed wheel sensor, wheel and tire, and suspension parts needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 77,000.
Other or unspecified, Engine, Apr 22, 2026
Driving and lost all power to truck annd lost control. Was able to coast truck with no accidents. all lights turned on dash board. Engine stating to make horrible noise. Cylinder 1 had a collapsed lifter which cause the failure. They replaced all lifters on the left side. They stated that batch of lifters were faulty. Requested to have the lifters on the right side replaced since they are the same batch but they refused. They would fix once or if they collapse but since they working they would not change them. Called GMC, reported it to them. The three people I spoke with had no idea about lifter problems and it was the first they had heard of it. Multiple complaints have been reported by customers. They did not want to give permission to replace the right side or extend the warranty. When the right side give out, if I am going at high speeds on the freeway, an accident could occur causing injury or death. I know they have a recall on prior GMC but my truck is not included.
Other or unspecified, Apr 21, 2026
Engine coolant control valve
Other or unspecified, Engine, Apr 20, 2026
Coolant control valve failing. Warranty not covering this part. Seems to be a manufactured issue. Happening on a lot of 2021 GMNC Sierras with the 3.0l Duramax.
Engine, Apr 18, 2026
My L87 engine has failed due to a manufacturing issue. The recall number for this issue is N252494000. Upon contacting GMC, they state that my VIN number is not included in this recall despite having the same exact issues. I took the vehicle into a mechanic as soon as a problem had arose.
Power train, Engine, Fuel/propulsion system, Apr 16, 2026
While driving into work, I noticed a knocking sound from the outside of the vehicle. Once parked, upon further inspection I narrowed down the area of the noise to the bottom rear of the engine/front of transmission. Fortunately, I was able to park in front of my office building and wasn’t stranded on the side of the road but under different circumstances it could've been the side of a busy highway or hours from home. I had the vehicle towed to the dealership I originally purchased from, the dealership was able to duplicate the issue with me present. Later that afternoon I was informed that the engine had failed and a replacement would be ordered. There was no prior indication of a problem or warning/CEL’s. The engine failed after the dealership had completed the engine recall ( pico test and 0-40W oil change ) related to the vehicle. I am reporting this in hopes that it helps with the investigation. This has been very disappointing for me as I have supported the brand of vehicle for many years. Only to have many issues under 80,000 miles and to lose confidence in the vehicle I purchased and the company.
Power train, Engine, Apr 13, 2026
The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving approximately 45 MPH, the transmission inadvertently shifted from drive (D) to first gear. The check engine warning light was illuminated. The vehicle was pulled over to the side of the road and then towed to the dealer, where it was diagnosed, and it was determined that the valve body needed to be replaced. The vehicle was not repaired because parts were not available. The manufacturer was notified of the failure. The failure mileage was approximately 103,000.
Engine and engine cooling, Apr 9, 2026
See attached document for complaint. INFORMATION, DETAILS, COMMENTS, DATES, AND NUMBERS ON RECALL 20211500 DENALI Recall Vehicle Information: All models of GM's with 6.2L gas engine (My personal truck I owned} • Recall date: April 23, 2025 650,000 + GM vehicles with 6.2L gas engine, years 2019-2023 • Manufacturer Recall Number: N2524944000 (letter issued by State of Washington Dept. of Licensing, PO Box 9020 Olympia, WA. 98507-9020 • NHTSA Recall Number: 25V274 • 2021 GMC 1500 Sierra Denali, x-tended cab, 4wh dr, 6.2 L gas engine • Vin #: WITH 6,400 MILES ON MY TRUCK May 15, 2025 • Went to local dealer, Becker Buick-GMC in Spokane, WA., to verify there was a recall on my truck and vin. #. Confirmed with there service department and sales person Jon Stone. • I was informed that the Dealership, service dept., and salesman Jon Stone, and Sales Mgr. Cameron could only say the following: "GMC DOES NOT have the tools made yet to verify if the engine will need to be replaced and would add me too the list and keep me posted." • I was informed at this time that t he issues with the engine were: engine could stop and start again at random; the engine start to smoke and stop; the engine could catch fi re whether it was running or not, or the engine could do ALL THREE things. • I was told to just keep driving the truck but watch for any of these issues. May 28, 2025 • Stopped in local dealer, Becker Buick-GMC, again to see if any updates. • Told GMC still had done nothing to develop the necessary tools to evaluate the engine and had no date to report or share with me on when they co uld. • Again, I was told to keep driving the truck and if I had a problem, Becker Buick would come and tow me. • Salespeople did ask if I wanted to just buy a new truck several times. They were impressed my truck only had 6400 miles on it and in such excellent shape. This was to be my retirement truck. June 5, 6, 7, 2025 • I visited several car dealers in the Spokane, WA. Area. Ford, Chevy, Dodge and Toyota. While looking at new/different vehicles to buy/trade I got much the same responses. "Sorry, we CAN" TTAKE YOUR TRUCK IN TRADE, until GM releases it off the recall list and states it is repaired. Everyone was aware of this massive recall by GM. June 18, 2025 • Not getting ANY ANSWERS, I called GMC Customer Service at 800.462.8782 and spoke with Cust. Service Manager, Brandy. • After long conversations, Brandy informed me that the tool(s) to check and evaluate the engine had NOT been developed yet and she could not give me a time line as to when that would be. She further confirmed that NO DEALER in the USA had the tools yet, even after I volunteered to drive to one. • I then said what I was wanting at this point, as their GMC dealer (Becker Buick) had told me to keep driving the truck, was I wanted either a long block engine replacement at NO CHARGE or at minimum and extended warranty of 125,000 miles on the complete engine and running gear. • I was informed by her that she could not honor either, and that any of her managers would tell me that I had to work directly with my local dealer. She offered no other solutions or advice, other then GMC would keep all the dealers updated on the tools, actions, and results. • I asked for the phone info and name of the Spokane area rep and requested a meeting with him. I was told I had to do that at local dealer level. June 24, 2025 • I met with salespeople Jon Stone and his manager to discuss options, if any, that I might have. • Told them about my full conversation with Cust. Service Brandy and how upset I was. • She {Brandy) stated that I would need to get the area rep info from them. They said he was due in town the next week and would give me a call so we could have discussions. (NOTE: next week came and went and I did NOT get a call. I was told he had to change his schedule last minute) • Now, I had two trips coming up in Sept. and Oct. that I was driving the truck to. One in Havasau A:Z.. And
Power train, Engine, Apr 8, 2026
I have a 2021 GMC Sierra 1500 AT4 3.0L diesel pickup truck with 98,500 miles. The coolant control valve failed on my vehicle and for some reason it is not covered under GM's special bulletin that covers this part 15yr/150,000. Ridiculous.
Engine, Apr 5, 2026
6.2 lifter failure at 44500 miles
Engine, Fuel/propulsion system, Apr 3, 2026
Began with a misfire on cylinder 5 code P0305. Replaced spark plugs, wires, and coil pack. Misfire still existed. Fuel injector on cylinder 5 was stuck open and had to be replaced. Misfire still existed. No spark from new coil pack on cylinder 5, replaced coil pack connector. Misfire still existed, but lifter tick became present. Removed cylinder head and found exhaust lifter on cylinder 5 was bad and needed replaced. Currently awaiting parts delivery (only available through GM dealer). Have been without vehicle for 7 weeks now. Was told this was most likely related to Active Fuel Management.
Engine, Apr 1, 2026
-The engine in my 2021 GMC Denali 1500 with the 6.2L engine failed its second engine with ~4,000 miles on the new engine. It is currently at GMC dealer waiting for a 3rd new engine. - Fortunately i was parked when the failure happened and the engine locked up. -Dealer confirmed that a valve dropped and damaged the cylinder wall. - There were no warning lamps or other indication that a failure was about to happen. -Current mileage ~91,000. First motor changed ~85,000 due to recall with previous owner.
Engine, Apr 1, 2026
There is a recall on the 6.2 motor that is in my truck at my last oil change they performed a pico scoop diagnostic on the truck said it passed and gave it the new type of oil and oil cap that was suppose to fix it. Now a couple months later I walk out start my truck to let it warm up and after starting all of a sudden the engine started nocking bad and loss of oil pressure and on dip stick. I looked it up and this is what happens when the engine fails due to the massive recall on the 6.2 engines. I called the dealer and they are having me tow the truck potentially at my expense for them to look at and decide if it falls into the category of the recall after they did the test, and at one point told me that cause they did the test it is no longer recalled. I am being told people who have had the engines replaced because of the recall that the replacement engines have failed as well. I have a 9 month old baby and this left me stranded and unable to pick him up from daycare I had to scramble to find somone able to do so. I'm concerned that this could have happened while driving and having him with me or being left stranded somewhere.I'm glad it didn't happen when I was dropping him off that morning and while I was driving And meanwhile while they look at the issue and decide weather this falls under there recall or not and while it gets repaired I'm left without a vehicle and to be honest I don't feel safe even if they do repair it as there seems to not be an actual fix to the situation. this is unsafe and unacceptable for the price we have to pay for these rigs and the safety regulations and standards we have, how is this even an issue.
Engine, Apr 1, 2026
THE ENGINE COMPLETELY SHUTS OFF WHEN I STOP AT A STOP SIGN OR STOP LIGHT. I HAVE BEEN STUCK IN TRAFFIC INTERSECTIONS ON SEVERAL OCCASIONS UNABLE TO MOVE WHEN THE LIGHT TURNS GREEN. EVENTUALLY THIS WILL LEAD TO ME GETTING REAR ENDED AND PUSHED INTO IN THE MIDDLE OF AN INTERSECTION. MY LIFE IS IN DANGER WHEN I DRIVE THIS VEHICLE. I GOT MY ENGINE REPLACED AND STILL THE SAME ISSUE IS OCCURRING WITH THE AUTO STOP AND START SYSTEM.
Power train, Mar 31, 2026
I believe the torque converter is failing. While driving approximately 38 mph and also 48 mph up to 51 mph the vehicle have a vibration feeling like driving on a rumble strip. If you maintain the same speed, the vibration continues if you speed up, slow down, or let off the gas it goes away. There are so many detailed explanations on forums and social media from other customers experiencing the same problem, but not seeing any recall made by GMC.
Other or unspecified, Mar 31, 2026
P1098 code coolant control valve fail service bulletin N252508341 my vin not covered but same motor and same part !
Steering, Mar 28, 2026
Loss of steering, erratic steering control. Steering locks up
Tires, Mar 24, 2026
Tires are LT275/65R20. While driving on interstate at approximately the speed limit and low 80 degree temperatures in South Carolina with proper placard pressure tire inflation checked two days prior, the truck developed a faint vibration which got worse over three or four miles. I slowed my speed and pulled over at next offramp and visually inspected truck for signs of vibration. Including looking over tires. It seemed like a drive line issue, however truck is a 2021 model with only 38,000 miles. After I could not find anything out of place I got back on the interstate to see if problems still existed. I was only traveling at 45 mph and vibration was getting worse, so I tried to slow and make it to next offramp when the driver side tire blew out causing me to have to quickly react to prevent having an accident. The tire tread and multiple parts of the truck inner fender guards and liner were thrown out into traffic and truck bed side is badly damaged. Prior to blow out there were no warnings on the dash board to to indicate any sort of issue and I verified tire pressures when I stopped after the vibration initially set in. The TPMS system was working properly at the time of the blowout. I have the tire if further inspection is warranted. My safety was at risk when tire blew out on the interstate along with vehicles traveling around me to avoid hitting the flying debris and tire tread. Further this was driver side tire and I had to change the tire on the side of the interstate with traffic right beside my vehicle. I called GMC and they said they would do nothing to help because they see tires as a maintenance item and truck is out of warranty period. I am a mechanical engineer having worked many years for major tire company as a tire design engineer. I am very familiar with load ratings, tire wear, life expectancies, and I believe theis tires failed prematurely. I bought this truck new and have always had tires properly inflated a never overloaded.
Electrical system, Engine, Mar 24, 2026
The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving approximately 50-65 MPH on an incline, the contact believed that the transmission was slipping or there was a misfire coming from the engine. The contact stated that the vehicle failed to restart automatically after the engine AUTO Start/Stop system was engaged after a complete stop. Additionally, the contact stated that after driving for a while, the vehicle went into LIMP Mode. The check engine warning light and other warning lights were illuminated. The vehicle was taken to the dealer to be diagnosed. The contact related the failure to GM Campaign Number: N252515590 (Corroded Ground Strap); however, the dealer had informed the contact that the vehicle was not covered because the VIN was not included and there was no warranty coverage on the vehicle. The vehicle was not yet diagnosed or repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was approximately 75,000.
Engine, Mar 23, 2026
L87 engine failure 4 months after it passed the recall test. Experienced shuddering and rpm fluctuation with the cruise control set. Was thinking torque converter. Got it replaced under warranty and the the issues were still there. A week after new TC the truck was running very rough driving down the road. Check engine light along with a low oil Pressure warning and Lost all engine power going 60mph. Would not re fire. Had to coast to a stop with no headlights on only fog lights. Truck is at dealership now will be needing a new engine. P0016 engine code. The truck was in the shop multiple times for misfire and rpm’s jumping and cruise control turning off on its own.
Power train, Mar 23, 2026
I've been to the dealership a few times due to the truck jerking violently under very light acceleration when its trying to shift gears. also there was a few times that the rear wheels have locked up while driving.