1,274 of the
11,357 complaints filed about the GMC Sierra 1500
are about the transmission —
11% of everything owners reported.
The worst model year for it is 2019.
1,274
Complaints
11%
Share of all complaints
25
Crashes
3
Fires
Transmission & Drivetrain complaints by model year
The contact owns a 2019 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the accelerator pedal was depressed and the vehicle started jerking and shaking before unintendedly accelerating. Additionally, the vehicle jerked and started to lose motive power. The dealer was contacted; however, the vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 108,000.
NHTSA complaint #11758287 — an unverified report by a vehicle owner.
Vehicle: 2026 GMC Sierra 1500 AT4 (3.0L LZ0 Duramax Diesel) Current Mileage: ~16,500 miles Check Engine Light Status: NO Check Engine Light active Description of Incident & Symptoms: •Interstate Incident: While driving at highway speeds, a severe drivetrain vibration occurred (felt like a rear wheel weight flew off). •Dashboard Warnings: Within 5 minutes, intermittent "Traction Control" and "Forward Collision Warning" alerts appeared on the dash, accompanied by a sudden drop in engine power. •Engine Noise & Idle: Once safely pulled over, the engine exhibited a loud mechanical knock and a very rough, unstable idle. •Extended Crank: After shutting the engine off and waiting a few minutes, restarting the truck took roughly twice as long as normal (long crank/delayed start)
NHTSA complaint #11758123 — an unverified report by a vehicle owner.
The contact owns a 2014 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle jerked and pulled to the right. No warning lights were illuminated. In addition, the contact stated that while driving over a bump in the road, the vehicle lost automotive power and shut off. The contact restarted the vehicle. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The manufacturer was not made aware of the failure. The failure mileage was approximately 230,000.
NHTSA complaint #11757905 — an unverified report by a vehicle owner.
My 2023 GMC Sierra 1500 SLT 4WD currently at 67659 miles was taken in to the dealer because of excessive jerk when accelerating or trying to reverse, diagnostic scan failed for check engine and ABS trouble codes. The scan return code PO747 indicating transmission pressure control solenoid “A” was stuck on for a predetermined period of time. The recommended repair is replacement of automatic transmission, solenoid control valve body. I’m aware that GM has issued a TSB 25–NA-255 and special coverage N24245441–02 addressing this exact failure on the GM 10 speed and that GM previously issued a related recall N242454440 addressing this exact failure on the GM 10 speed transmissions, and that GM previously issued a related recall for this citing rear wheel lock up risk associated with transmission valve condition. My vehicle scan showed an ABS failure at the same time as a transmission. code, consistent with the safety risk. GM has already acknowledged and its own recall documentation however I was told to contact NHTSA to document the safety risk and request investigation of the scope of this defect across affected models years and vehicles as mine seems to have fallen short. I previously owned a 2021GMC vehicle same model that experience the identical transmission valve body failure that vehicle could not be repaired in a reasonable time and I ultimately experience financial loss and had to replace a vehicle now I’m experiencing the same defect on the vehicle purchased (this one) with significantly fewer miles than would be expected for a major transmission failure, indicating that this may be a reoccurring manufacturing design defect rather than an isolated incident. Thank you for your time and I hope this issue can be resolved as I do love the truck otherwise however safety first. Thank you
NHTSA complaint #11757965 — an unverified report by a vehicle owner.
I was driving north/east on [XXX] just outside of [XXX]. After accelerating to give another driver room to move out of his lane that was ending, I lost propulsion/power. The Sierra went into Neutral and told me something like "Press Start to resume". I had to immediately get off the interstate as I was rapidly losing speed. I was able to pull over to the shoulder of the interstate on the right, just before exit 2. After getting the vehicle parked, I was never able to restart the vehicle. The motor would not turn over. The display screens kept cycling between a blank display and a display that looked like the vehicle was on but the engine never turned on. When I tried to start the car, I got a message of "conditions not correct for shift". We could not even get the vehicle into Neutral. I used OnStar to get State Patrol to show up and put lights behind us for safety. OnStar should have a recording of this call. This was on Saturday XXX in the ballpark of 2:30 pm central time. I would imagine the officer also filed a report, but I did not get it. The vehicle was towed to Billion GMC in Iowa City. Billion GMC said their initial suspicion is the 6.2L motor failed / locked up on us as this is know issue that is subject of a class action lawsuit. These vehicles ARE NOT SAFE to be on the highway, someone is going to get seriously injured, please do everything you can to get these 6.2L engines off the road before someone dies. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11757264 — an unverified report by a vehicle owner.
At approximately 85,000 miles, the engine in my 2019 GMC Sierra 1500 seized. The vehicle was parked when it occurred. This created a safety risk because an engine seizure can cause sudden loss of propulsion in traffic. Before the failure, I didn't notice anything that would raise any alarms. The problem was inspected and confirmed by a GMC dealer, which diagnosed the condition as an engine seizure. The failed engine is not available for inspection. I am not aware of the precise internal cause beyond the dealer’s diagnosis.
NHTSA complaint #11756621 — an unverified report by a vehicle owner.
At approximately 85,000 miles, the engine in my 2019 GMC Sierra 1500 seized. The vehicle was parked when it occurred. Inability to start. This created a safety risk because an engine seizure can cause sudden loss of propulsion in traffic. Before the failure, I did not notice any red flags. The problem was inspected and confirmed by a GMC dealer, which diagnosed the condition as an engine seizure. The failed engine is not available for inspection. I am not aware of the precise internal cause beyond the dealer’s diagnosis.
NHTSA complaint #11756622 — an unverified report by a vehicle owner.
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 complaint #11756447 — an unverified report by a vehicle owner.
The contact owns a 2019 GMC Sierra 1500. The contact stated that while at a red traffic light, the vehicle accelerated unintendedly, and the vehicle shuddered with an abnormal dinging sound coming from the vehicle. The message "Transmission Hot - Idle Engine" was displayed on the instrument panel. The vehicle was taken to a dealer where it was diagnosed and determined that the transmission was slipping, overheating, and that the transmission needed to be replaced. The contact researched and became aware of a recall; however, the VIN was not under recall. The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 126,098.
NHTSA complaint #11756219 — an unverified report by a vehicle owner.
transmission shift hard and slipping. When step on gas to go faster transmission shifts really hard like going drop on ground. Sometimes wont shift at all only goes up to 69 till left off gas and then transmission will shift. Start happening with about 10000 miles on truck and GMC said this is normal. Now need a torque converter and shift module in it.
NHTSA complaint #11756150 — an unverified report by a vehicle owner.
Was traveling home and started losing power going up a hill on XXX. The truck was surging, the check engine light came on and an audible warning of no (low?) oil pressure. The truck shut off on a busy interstate highway and barely got onto the shoulder. The tow truck driver had to lay on the ground with part of his body in the lane of travel to place "skids" under the rear tires because there is no way to place this vehicle in neutral for a tow without a special GM tool. When I contacted Harry Robinson GMC service center in [XXX], they told me that it was no longer a safety recall because the truck had passed diagnostics and new, high viscosity oil was put in the truck XXX. The GMC app says code P0016 which is the dreaded 6.2L camshaft to crankshaft alignment that accompanies engine component failure. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
NHTSA complaint #11755885 — an unverified report by a vehicle owner.
The failure to have proper viscosity oil along with manufacturing error resulting in failure of lifters, cam shaft, and crank shaft all needing replaced. Repair totaled over $10,000
NHTSA complaint #11755433 — an unverified report by a vehicle owner.
My 2015 GMC Sierra 1500 SLE has the 6L80 transmission. While traveling on the interstate with my fiancé, the transmission failed. It was towed to a garage and they informed me that it needed to be replaced.
NHTSA complaint #11755314 — an unverified report by a vehicle owner.
"While driving, the vehicle suddenly experienced a flashing check engine light, an Electronic Stability Control (ESC) warning light, and violent steering wheel vibrations. The vehicle suffered a severe loss of power and misfired, creating an immediate traffic hazard. The dealership diagnosed the issue as a catastrophic mechanical lifter failure on the 5.3L V8 Ecotec engine with Dynamic Fuel Management (DFM). Despite the dealer replacing an entire bank of lifters, the engine continues to misfire and vibrate. This premature valvetrain failure at only 36,000 miles is a known design defect that causes sudden engine stalling and disables critical safety features like stability control while the vehicle is in motion, presenting a severe crash risk."
NHTSA complaint #11755269 — an unverified report by a vehicle owner.
The contact owns a 2026 GMC Sierra 1500. The contact stated that while her husband was driving approximately 10 MPH, the vehicle unexpectedly shut off and independently shifted into park(P). The contact stated that previously, while the vehicle was idling in a parking lot, with air conditioner activated, the Auto START/STOP feature engaged, and the vehicle shut off. The message “Service Transmission” was displayed. The vehicle was taken to a local dealer and was diagnosed with transmission failure. The vehicle was not repaired. The manufacturer was not contacted. The failure mileage was approximately 2,000.
NHTSA complaint #11755200 — an unverified report by a vehicle owner.
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 complaint #11754985 — an unverified report by a vehicle owner.
Ever since I bought this truck new, I noticed a lot of metal shavings and debris in the oil filter every single time I changed the oil. I took it to the dealership multiple times to have this looked into before the engine recall came out. The dealership took pictures of the metal and sent them to a General Motors engineer, but the engineer just told them it was "normal." Later on, the truck went in for the official recall inspection, passed the PICO test, and nothing was fixed. Then on August 4, 2026, I was driving on a crowded expressway right through a construction zone with absolutely no shoulder to pull over on. Out of nowhere, the truck started hesitating badly, lost power, and the engine started making a really loud knocking noise. It was barely running, and it was incredibly dangerous because there was nowhere to go and traffic was heavy. Luckily, I was able to limp the truck along just far enough to clear the construction zone and pull over safely.
NHTSA complaint #11755085 — an unverified report by a vehicle owner.
I am submitting this complaint to report what I believe is a serious safety-related defect involving the General Motors 6.2L L87 V8 engine installed in my 2026 GMC Sierra Denali. On July 10, 2026, while driving on a public highway near Bogata, Texas, the engine suddenly began making severe mechanical noises before catastrophically failing without warning. The engine seized completely while the vehicle was in motion. At the time of failure, the truck had only 13,517 miles. The sudden loss of engine power left my wife and me stranded on the roadside. Had this occurred while crossing an intersection, merging into traffic, passing another vehicle, towing a trailer, or traveling in heavier traffic, the consequences could have been far more serious.
NHTSA complaint #11755053 — an unverified report by a vehicle owner.