RoadVitals

2021 GMC Sierra 1500 Powertrain (other) Problems

Owner-reported complaints naming the powertrain system, filed with NHTSA

Data refreshed

Powertrain (other) reportsComplaints are reports submitted to NHTSA by owners and drivers. NHTSA does not verify most reports before publishing them, and a complaint does not establish that a defect exists. Volume is influenced by how many of a vehicle were sold, how long it has been on the road, and how much attention an issue has received.
131
Latest Aug 12, 2026
Share of all reportsThis category as a share of every owner report on file for this model year. One report can name more than one component, so the categories overlap.
25%
of 533 total
Crash or fire reportedReports in this category whose submitter recorded that a crash or a fire occurred. The reporter's own answer on the NHTSA form, not a verified finding.
0
Injuries or deaths reportedTotals the submitters entered on their own reports in this category. Not verified by NHTSA and not a casualty statistic.
0

What this page shows

Powertrain reports that are not specifically the engine or transmission — driveshafts, axles, transfer cases and differentials. Every record below is an owner-reported complaint about the 2021 GMC Sierra 1500 submitted to NHTSA — not a confirmed defect, not a recall and not a manufacturer bulletin. 131 reports on file name it.

Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.

Owner reports naming powertrain

The 25 most recent of 131, in the owner's own words

Powertrain (other)
Filed Aug 12, 2026

Transmission Valve Body failure. - Caused wheels to lockup momentarily and killed the engine with sudden loss of propulsion. Link to video of incident: [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID
11756447
Incident
Aug 4, 2026
Powertrain (other)
Filed Aug 5, 2026

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the transmission was shuddering, especially while driving uphill. The dealer was contacted, and the vehicle was diagnosed and determined to have a failure associated with a GM TSB for the incorrect transmission fluid inside the transmission reservoir. The vehicle was not yet repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 38,875.

NHTSA ID
11754985
Incident
Jul 15, 2026
Mileage
38,875 mi
EnginePowertrain (other)
Filed Jul 30, 2026

2021 Harley Davidson Sierra 4WD, 6.2L L87. Started the truck in the morning and immediately heard intermittent, very loud banging noise coming from engine. Shut truck down quickly and had it towed to dealer. Diagnosis was bent pushrods & failed lifters which were replaced under warranty. Factory warranty expired only 4 months after this failure, and the recall does not include my VIN so I did not get an extended warranty or any other protection. GM has yet to even reimburse the tow bill. Completely unacceptable for a truck that was well over $100k when new.

NHTSA ID
11753693
Incident
Oct 11, 2025
EnginePowertrain (other)
Filed Jul 22, 2026

On June 25, 2026, at approximately 84,000 miles, while traveling approximately 60-65 mph on Highway 121 in a posted 65 mph zone, driving my 2021 GMC Sierra 1500 AT4 equipped with the 6.2L L87 engine, multiple warning messages suddenly appeared, including “Check ESC,” “Check Parking Brake,” “Check Brakes,” and “Check Engine.” The engine began operating abnormally. I drove directly to Sewell GMC because I was concerned that the engine could fail or the vehicle could lose propulsion while in traffic. There was no crash, fire, or injury. Sewell GMC inspected the vehicle and confirmed catastrophic internal engine damage. The technician found metal debris in the engine oil and oil pan, damaged internal bearings, and camshaft/lifter damage. Sewell advised that the complete engine must be replaced. The vehicle remains at the dealership, has not yet been repaired, and the engine and failed components should be available for inspection. Before this incident, I had not experienced warning lights or symptoms indicating that an imminent catastrophic engine failure would occur. GM and the dealership advised that my VIN is not included in the current L87 engine recall because the engine was built in 2020. However, the diagnosed bearing damage, metal contamination, and catastrophic engine failure appear similar to the engine failures addressed by that recall. I am reporting this because an unexpected internal engine failure while driving creates a serious risk of loss of propulsion and a collision.

NHTSA ID
11752087
Incident
Jun 25, 2026
Powertrain (other)
Filed Jul 15, 2026

The 10 speed automatic transmission shakes and jumps between gears. The transmission also shakes and rumbles at cruising speeds. The diesel engine version of this truck is already recalled. My truck is a gas engine and should also be recalled. This is the same defective 10 speed transmission used in all GM vehicles and recalled in many. This vehicle needs to be recalled and fix before the wheels lock up and kill someone.

NHTSA ID
11750566
Incident
Jun 1, 2026
Powertrain (other)
Filed Jul 9, 2026

transmission shuddering, harsh or delayed shifting, and erratic gear changes. The truck jerks really bad during each shift of the ten speeds. A vibration or shudder typically occurring at speeds between 25-65 mph under light throttle. Also makes a bad noise every times it’s shifting. I have no lights on the dash and the gmc app tells me everything is fine when clearly it’s not . I see there’s a recall for my year and make but for some reason my vin doesn’t fall in the category

NHTSA ID
11749233
Incident
Dec 31, 1969
Powertrain (other)
Filed Jul 8, 2026

My car suffered a catastrophic engine failure, metal schards were found in the oil filter and was left out of the 2021 recall 25V274. The in service date of vehicle is March 13, 2021. The car was 83 days out of warranty when the engine failed. The truck has 47,000 miles on it. They are now trying to charge us, barter with us. They have gone from $2800 for repair, negotiated down to $100 to sign this off as a good will repair stripping us of lemon law rights and future recall remedies. Car is currently sitting at the dealership.

NHTSA ID
11749076
Incident
Jun 4, 2026
Fuel systemPowertrain (other)
Filed Jul 6, 2026

Dashboard lit up with engine light and stated that there's no compulsion

NHTSA ID
11748647
Incident
May 21, 2026
Powertrain (other)
Filed Jun 23, 2026

The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the brake pedal was depressed, but the vehicle continued to move forward. There was no warning light illuminated. The vehicle was taken to the dealer and was diagnosed with transmission failure. The contact stated that the valve body and torque converter needed to be replaced. The dealer informed the contact that the transmission might need to be replaced. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 65,561. The VIN was unavailable.

NHTSA ID
11745943
Incident
Jun 12, 2026
Mileage
65,561 mi
EngineFuel systemPowertrain (other)
Filed Jun 17, 2026

While driving my vehicle, the engine and transmission lost power and the check engine light came on. The vehicle went into limp mode and engine propulsion was limited. Had I been traveling at a faster speed, this would have been very unsafe. After coming to a stop, placing the transmission in reverse did not move the vehicle and there was a grinding noise. I was able to savely move forward in limp mode, but the shifting was harsh. I was able to find an empty parking lot to safely park. The truck was towed to Jim Winter dealership in Jackson MI for inspection.

NHTSA ID
11744736
Incident
Jun 17, 2026
ElectricalFuel systemPowertrain (other)
Filed Jun 16, 2026

So I made an appointment to have my truck recalled and the Wednesday before I took it, and it cranked no start and I called the dealership. Ask if they had any other those like this and they said that it could be the fuel injector module and so I got it to a mechanic shop to read the codes and it gave me a code p062b and I asked the dealership to look into it and they never figured out what we were not wrong. I just testing the battery. Well, then I got it back after the recall was done and new transmission valve body put in and about 30 miles down the road it started to shake violently and had a flashing engine light so I got it home called the dealership the next morning because they were closed set up another appointment got it to the dealership dealership said it had a couple misfires but since it wasn’t over 100 they weren’t concerned even though I’m pretty sure it is related to the fuel model going out because it has been cranking rapidly whenever I try to start it, but they won’t do anything to figure out what’s wrong?

NHTSA ID
11744628
Incident
Jun 5, 2026
Powertrain (other)
Filed Jun 16, 2026

When pressing on the gas, especially when moderately accelerating, the truck experiences severe shaking, which interferes with acceleration, as well as causing the truck to "jump" when the transmission gear "catches", even while driving. When the truck is at a full stop and the engine is auto off, when it restarts, it does so frequently when it reengages that it causes a physical "jump" in the vehicle, causing the driver's foot to come off the brake pedal. This has been most noticeable since my vehicle hit about 70k miles. I currently have 84k miles. I engaged the dealer and was told the transmission is out of warranty. I see that other GMC Sierra models suffer similar problems and recalls have been issued to GMC that they must repair those vehicles. Despite that, my vehicle is not included in any current recall program.

NHTSA ID
11744554
Incident
Jun 15, 2026
EngineExterior lightingPowertrain (other)
Filed Jun 13, 2026

While coasting down or under very light acceleration between 12-20 mph the vehicle has a shudder like driving over a highway rumble strip. While cruising on the highway at 65+ mph, the vehicle has a light shudder or vibration. Vehicle has been checked numerous times for wheel and tire inconsistencies. Brake pads and rotors have also been replaced with no change in issue. Headlights daytime running light changes color from bright white to purple during warm weather. The vehicle has been to 3 different GM dealerships and they acknowledge the issues but do not provide a resolve.

NHTSA ID
11743882
Incident
Jun 13, 2026
ElectricalPowertrain (other)Steering
Filed Jun 1, 2026

power steering locked up while driving. has been inspected and repaired by manufacturer. recall.

NHTSA ID
11741190
Incident
Mar 29, 2026
ElectricalPowertrain (other)Steering
Filed Jun 1, 2026

power steering locked up while driving. multiple dash lights turned on, on its own after the issue, 4wd, emergency brake, abs, and other ones im not sure what they are. took it to the dealership for a recall and told them the issue that happened.

NHTSA ID
11741189
Incident
Mar 29, 2026
Driver assistanceEnginePowertrain (other)
Filed May 30, 2026

The truck randomly will not detect that it was shifted into park. Shifting between gears and back to park does not automatically fix the the issue and has taken up to 10 mins to turn the truck off. The adaptive cruise controls stopped working and can still use regular cruise control. Just not adaptive. It appears greyed out. The truck has thrown the error code: P1098, Engine Coolant Control Valve Position Sensor Minimum Stop Performance. The truck would go into limp mode until the error was cleared. This error has appeared 4 times over the past five months. The most recent date of it happening was today. 06/30/2026

NHTSA ID
11741078
Incident
May 30, 2026
Powertrain (other)
Filed May 26, 2026

The truck has a studder that comes from the transmission when at highway speeds. the studder can be felt at random intervals (seconds) from all passengers. The studder is also present on starting up a slope or accelerating from a stop at a slow pace. when accelerating slowly the jerk is more prominent. We have taken it to the GM Dealership, they confirmed the issue was present. The dealership said the GM guidence was to 1st try a re-program and then replace the torque converter. The program flash was unsuccessful, then we paid $4000 to change the torque converter. The Tech stated that this was the GM suggested fix, but noted that we are changing the fluid also which could mask the issue if it is the valve body causing an issue. The replacement torque converter and fluid did somewhat reduce the issue for a short period of about 2 months before it has returned as it did before. The next option from the dealership is in excess of $8,000 for a remanufactured transmission which is outside our reasonable spend, when we dont expect the remanufactured transmission will have any better valve body components. The recent recall did not cover my gas 6.2L sierra 1500, although it clearly is insufficient stating that it just a warning that there is a safety risk present. The valve body of the transmission appears to be an issue across all models and the recall addresses that it is present. We continue to drive this as the primary family vehicle with the hesitation and jerking present as GM dealer offered no support other than $8,000 remanufactured transmission on top of the $4000 we already spent. I believe the recall was insufficent in covering the Gas models with the exact same transmission and known issue. I also believe the offered solution continues to put those driving at risk.

NHTSA ID
11740118
Incident
Apr 1, 2025
EnginePowertrain (other)
Filed May 12, 2026

Right after i bought the car I had a very bad misfire on cylinder 1, the car would shake at idle. Took to dealership and they said they replaced all the spark plugs and replaced cylinder 1 coil. about a week later the misfire and shaking started again but this time it would come and go. the check engine light would be on then it would go away for a bit and then come back on over and over again. The only thing that seemed to work is if i disabled the stop and go start system and put the car in L9 to disable the AFM. This seems to work and I have since bought a disabler for these systems. However, there is still a vibration at idle and i feel that its a temporary fix to a bigger issue. This is my daily driver and constantly have my children in the car and just want the car to be safe for everyone. The transmission downshifts rough and at times seems to slip/lock up while driving. I haven't brought it to the dealership for this as of yet.

NHTSA ID
11737211
Incident
Jun 1, 2025
Powertrain (other)
Filed May 5, 2026

Coolant control valve has failed and caused the check engine light to occur is available for inspection. Could cause the car to overheat and cause harm to myself or others Yes has been confirmed by dealer No GM has a special coverage out for the specific vehicle and model years for this vehicle, but are stating that my vehicle does not pertain to that coverage.

NHTSA ID
11735894
Incident
May 3, 2026
EngineFuel systemPowertrain (other)
Filed 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.

NHTSA ID
11731720
Incident
Apr 15, 2026
EnginePowertrain (other)
Filed 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.

NHTSA ID
11730861
Incident
Feb 9, 2026
Mileage
103,000 mi
EnginePowertrain (other)
Filed 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.

NHTSA ID
11729967
Incident
Oct 7, 2025
Powertrain (other)
Filed 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.

NHTSA ID
11728402
Incident
Jan 1, 2026
Powertrain (other)
Filed 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.

NHTSA ID
11726248
Incident
Feb 4, 2026
Fuel systemPowertrain (other)
Filed Mar 20, 2026

The DEF tank in my truck is defective and its the second time in the last 14 months it has broke. The part is now back ordered and according to the dealership this is a nationwide issue regarding these specific trucks. I have contacted around 10 dealers in my area and all tell me the same thing that they have multiple trucks waiting on the same issue. I have not had my truck for over 2 months and have no idea when i will be getting it back due to dealership having no idea when the part will be released due to the back order. This seems to a huge issue with these trucks and GM is doing nothing to help resolve it. I've reached out to GM directly and get no assistance and now have made 2 payments on my truck and the dealership refuses to give me a loaner vehicle. i am looking for some help or relief on what to do to go about my issue

NHTSA ID
11725796
Incident
Jan 24, 2026

Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers.

Other components reported on this vehicle

Categories with enough reports to have a page of their own

Elsewhere on this vehicle

Data sources

Data on this page last refreshed .