2018 GMC Sierra 1500 Owner Complaints

Head gasket failure and overheating. After fixed, power steering has just failed during driving. Will have to have it towed to shop

NHTSA ID

11756121

Incident

Aug 10, 2026

THE FRONT PASSENGER SIDE SEAT BELT RETRACTOR IS FAILING TO RETRACT. I HAD A PASSENGER IN THE VEHICLE AND AS WE CAME TO A STOP IN MY DRIVEWAY TO EXIT THE VEHICLE SHE UNHOOKED (RELEASED) THE SEATBELT AND IT WILL NOT RETRACT. THE SEATBELT IS NOW CURRENTLY EXTENDED OUT AND WILL NOT RETRACT BACK INTO THE RETRACTOR. I PURCHASED THE VEHICLE TODAY 08-05-2026, I CALLED THE DEALER I PURCHASED IT FROM AND THEY STATE THAT THERE IS NO RECALL ON THE VEHICLE WITH THIS ISSUE. I DID LOOK THE ISSUE UP ON GOOGLE AND INFACT IS STATES A PROBLEM WITH THE SEATBELT RETRACTOR FOR MY VEHICLE. I SENT THEM A SCREENSHOT OF THE CONFIRMATION FOUND AND THEY DECLINE TO ACKNOWLEDGE A REPAIR STATING THERE IS NO RECALL. I WAS ABLE TO MANUALLY FEED THE BELT BACK INTO THE RETRACTOR, IT WAS EXTREMELY DIFFICULT BUT I SAT IN THE SEAT TO DUPLICATE THE ISSUE AND IT WILL DUPLICATE. THE SEATBELT IS CURRENTLY EXTENDED AND WILL NOT RETRACT AUTOMATICALLY. THE SHOULDER STAP WILL NOT FIT SECURELY AROUND A PASSENGER AT THIS TIME. I HAVE HAD NO PRIOR USE OF THE VEHICLE UNTIL TODAY AS I PURCHASED IT FROM A REPUTABLE DEALER WHO STATES THEY DID A FULL INSPECTION OF IT PRIOR TO SELLING BUT APPARENTLY THIS ISSUE WAS NOT REPAIRED PRIOR TO SELLING IT.

NHTSA ID

11755159

Incident

Aug 5, 2026

ENGINE FAILURE, 5/3/22, 23,987 MILES, ALL LIFTERS WAS REPLACED UNDER WARRANTY, ENGINE FAILURE, 7/6/26, 46004 MILES, TOOK TRUCK IN FOR OIL CHANGE AND WHEN RETURNED HAD A TICKING NOISE. DEALERSHIP NOTIFIED ME THAT CAMSHAFT ISSUES AND METAL DETECTED IN OIL. ENGINE NEEDS REPLACED. 6.2 V8 2018. TURPIN MOTORS, GENESEO, IL HAS DONE ALL SERIVCE ON TRUCK. NO WARNING LIGHTS OR CODES. VEHICLE IS IN MY GARAGE AND AVAILABLE FOR INSPECTION. I OPENED CASE WITH GM #105652237. DEALERSHIP OPENED CASE ON GM PORTAL ALSO. RESPONSE FROM GM IS THAT TRUCK IS OUT OF WARRANTY

NHTSA ID

11754023

Incident

Jul 6, 2026

Vehicle Details: 2018 GMC Sierra 1500 Z72 4x4, 5.3L V8 EcoTec3 engine, VIN: [XXX] Mileage at time of incident: 220,000 miles Location: [e.g., Little Rock, Arkansas area or specific road/highway – please provide if desired] What happened: The 5.3L V8 engine’s hydraulic roller lifters failed. One or more lifters collapsed, stuck, or lost proper oil pressure/operation. This led to improper valvetrain function, causing loud ticking/knocking noises, cylinder misfires, significant loss of engine power and performance, and internal engine damage (such as camshaft lobe wear or related components). Component or system that failed or malfunctioned: Hydraulic valve lifters (camshaft followers) in the engine valvetrain, associated with the Active Fuel Management (AFM) system. The failed lifter(s) and related components are available for inspection upon request. How safety was put at risk: The engine malfunction resulted in sudden or progressive power loss and misfiring while driving. This reduced the vehicle’s ability to accelerate or maintain speed, especially in traffic or on highways, creating a hazardous situation that put my safety and the safety of other road users at risk of collision or breakdown. No accident or injuries occurred , or other symptoms prior to the failure with details recall, e.g., ticking noise timeline, misfires Has the problem been reproduced or confirmed by a dealer or independent service center? “Yes, confirmed by shop inspection” Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? [Yes] Additional notes: Repair estimate is approximately $20,000 (likely due to extent of internal damage requiring major engine work or replacement). This failure aligns with a well-documented issue in GM 5.3L engines equipped with AFM. Vehicle status parked INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11743611

Incident

Jun 11, 2026

Power steering went out for 2-3 seconds as I was making a turn into a street , this happened twice to be exact

NHTSA ID

11743173

Incident

Jun 7, 2026

Incident description: On three occasion I have had the same catastrophic Engine failure putting myself and my family along with the general public in harms way. Starting March of 2022 while driving at approximately 60 MPH on the West Shore Expressway my truck experienced a sudden and total loss of motor power. My engine stalled out and I lost my ability to safety steer and stop my vehicle. This all happened during rush hour while driving in the left lane of traffic. This sudden loss of power forced me to maneuver the vehicle to the right shoulder of the expressway across the right lane of traffic. As there was no shoulder to pull over on the left side of the highway. This created an immediate crash risk for myself and other drivers. Upon inspection at the authorized GMC dealership where I purchased the truck new, a certified mechanic determined that the engine experienced a complete failure requiring replacement or rebuilding of the engine. I paid to have the engine rebuilt at the dealership. The second instance was similar to the above incident. Once again I paid for the repair. The third instance was more dangerous as when my trucks engine failed it almost caused an accident. As of today my truck is still sitting in the dealership for over 6 months and no one from the dealership or manufacturer will give me an answer on what has to be done now. This patter of sudden repeated engine failure clearly indicates a systemic safety defect that extends beyond normal wear and tear. I urge the NHTSA to open a defect investigation into the 2018 GMC Sierra 1500 engine systems.

NHTSA ID

11741547

Incident

Mar 1, 2022

Paint flaking top above windshield within one year of ownership! Paint flaking on left rear door within last month!

NHTSA ID

11738475

Incident

Apr 4, 2026

The transmission has always been rough. It has now gone out at 75,000 miles. This transmission issue really seemed to get worse about 50,000 miles. But when I called the dealer, they said they were backed up and couldn't get to it for 9-12 weeks (Covid excuses at that point). Then, it really had an issue going down a large grade into [XXX] . But the issues seemed fairly intermittent. I had an independent shop who said it was hard to tell if it was intermittent. They didn't find metal shavings at the time. ADDITIONALLY, it has also always been a little rough driving. A mechanic looking at it today told me there are no sway bar links at all. This truck has not been modified. This had to have come off the line faulty. Among all the other things. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11738210

Incident

May 5, 2023

I’ve owner the vehicle since new. My A/C condenser has failed 3 times, meaning I’m now about to be on my 4th. The welds are weak and it cracks in the same spot 95% of the time. It should last more than a 2 year average.

NHTSA ID

11728308

Incident

Mar 23, 2026

Premature frame rot

NHTSA ID

11724945

Incident

Mar 16, 2026

The contact owns a 2018 GMC Sierra 1500. The contact stated that while driving approximately 45 MPH on bumpy terrain, the driver’s and passenger’s side curtain air bags deployed unexpectedly. No warning light was illuminated, and there was no impact to the vehicle to cause the air bags to deploy. The vehicle was taken to a local independent mechanic, where it remained for further investigation. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 80,000.

NHTSA ID

11722171

Incident

Feb 19, 2026

Mileage

80,000 mi

1. Electronic power steering modular issue. My 2018 GMC SEIRRA 1500 CREW CAB JUST LOST ALL POWER STEERING. THEN WHEN I PARK IT. Assist notifications come on, ABS notices, BRAKE light stays on, trailer/tow notifications, trailer assist, parking brake, etc SUDDENLY A LOUD thump & feels like the whole truck just drops like 5” inches, settling. I cannot afford an inspection (ID theft in 2025, compromised all accts & all credit cards) BUT. It IS available as long as cost is covered by YOU !! 2. Lucky it happened in a grocery store parking lot. However not expecting power steering to go out, almost hit a pedestrian. 3. No it has not Ben inspected yet I can’t afford the bill 4. No it has not been reported what for I didn’t hit anybody and the cops in this area they could give her rats ass they don’t make a report the question you like you’re like a criminal. 5. No warnings or anything until it happened that day leaving the grocery store. There is absolutely no notification it was gonna happen. It ran fine when I parked it to grocery shop Come back out & I could barely back out to leave. I can lift up my had fatboy if needed so I’m sure turning a steering wheel…. lol Thnx a lot If I could figure out what part needs to be changed out or you could cover the parts needed. I do work in cars or have in the past, I don’t like the new ones, but this seems simple enough if I knew exactly what part I needed to pull out change out or I see that there’s recalls on previous vehicles and GMC after2020- 24 but I don’t see 2018 didn’t happen so I like to say whoever created that electronic steering can take that module along with the harness and they know exactly where they can put it don’t they I’m just saying as a used to be not sure now a GMC supporter, but I’m starting to think twice now if I

NHTSA ID

11721830

Incident

Feb 18, 2026

I’ve gone through two transmissions on my 2018 gmc sierra 1500 both times the same issue. The gears are shot, hard shifting. Vehicle is well maintained. Both transmissions one original equipment and second bought at the dealership the truck was bought both only lasted over 80000 miles. Driving the truck loss of power or torque is noticed, then a hard shifting. Checked fluid all was good not seeing metallic shavings. Then the overheating of the transmission, faulty valve replaced with aftermarket bypass and did transmission flush. But each occasion there was an incident I would’ve driving on the interstate and vehicle would lose power and almost hard stop and cause a crash. Then vehicle would only go in reverse both times the transmission gave out. The only warning light that ever came on was a transmission overheating and nothing else. I’m currently in the process of having to get another transmission because of the same issue again. Vehicle was seen by a technician and deemed the transmission was shot again.

NHTSA ID

11721211

Incident

Feb 6, 2026

The contact owns a 2018 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle jerked abnormally hard. No warning lights were illuminated. The vehicle was taken to the dealer, where it was diagnosed with transmission failure. The contact was informed that the transmission needed to be replaced. The vehicle was repaired; however, the failure reoccurred. The vehicle was taken to the dealer, where it was diagnosed and determined that the transmission was failing. The contact was informed that the transmission needed to be replaced. The vehicle was not repaired. The contact was informed that the repair was not covered under warranty. The transmission was replaced two years ago. In addition, the contact stated that the original transmission had failed at 130,000 miles. The manufacturer was not made aware of the failure. The failure mileage of the second transmission was approximately 40,000.

NHTSA ID

11719391

Incident

Aug 20, 2025

Mileage

130,000 mi

The contact owns a 2018 GMC Sierra 1500. The contact stated that while driving at various speeds, there was an abnormal vibration in the steering wheel. There was no warning light illuminated. The contact stated that the tires were replaced, and the wheels and bearings were inspected by an independent mechanic, but no failure was found. The independent mechanic related the failure to an undisclosed transmission recall; however, the dealer informed the contact that the VIN was not under recall. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure, but no assistance was provided. The failure mileage was approximately 28,000.

NHTSA ID

11718452

Incident

Jan 17, 2026

Mileage

28,000 mi

The contact owns a 2018 GMC Sierra 1500. While starting the vehicle, it was shaking violently, with reduced power. The vehicle was restarted and worked as designed. Upon research, the contact associated the failure with NHTSA Action Number: PE25001 (Engine and Engine and Cooling). The vehicle was taken to an independent mechanic who determined there was metal in the engine, and there was a misfire coming from cylinder #2. The mechanic recommended that the engine be replaced. There were loose wires from the ECM, and the failure halted after the mechanic secured the wires. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The approximate failure mileage was 150,000.

NHTSA ID

11714207

Incident

Jun 1, 2024

Mileage

150,000 mi

I OWN A 2018 GMC SIERRA DENALI ULTIMATE, The truck has the 6.2 engine which had the lifter issue as stated with the current situation. At the time, the truck had 37,000 miles when the issues started. I purchased the truck from Andy Mohr with 8806 miles on it in November of 2019. I worked overseas for the DOD so that’s why the miles are low. After I got it fixed, ($4500 dollars at Hare Chevrolet) I experienced the transmission shake while driving home from work with my children in it. The transmission was shaking so bad the whole cab was rocking.That repair was $3,300. Now, the truck has piston slap and rod issues and currently at Hare Chevrolet for service. I was told I need a full rebuild ($12,000 dollars or a new engine $14000 dollars). As a retired Air Force veteran, I didn’t expect issues like this, especially when I baby the truck and it currently has 40,530 miles. I had regular oil changes and service, yet now stuck with a high class truck that has serious issues that seem to be ignored by GM and Andy Mohr GMC. Andy Mohr sold me an extended warranty at time of purchase but I paid for a year and a half that wasn’t usable. If I had that warranty I would be covered now.But besides that, it’s a Denali, I shouldn’t be having a new engine at 40,530 miles. I am happy that there is an investigation but it needs to be widened because my truck was right before the new model rollout but I am having the same issues. If needed, I have all my receipts and information and will provide the service rep at Hare. The reason why its at Hare vs Andy Mohr is due to me catching them not fully servicing my truck and joy riding my Camaro ZL1 after an oil change before I went home for a funeral.

NHTSA ID

11712288

Incident

Oct 22, 2025

The lifters in my engine collapsed. This caused a push rod to be bent and the cam shaft to be damaged causing thousands to fix. While I was driving. I could feel the engine malfunction causing my speed to significantly decrease. The vehicle was fixed through an independent mechanic. Mechanic stated that the active fuel management system is the cause for the lifter collapse. There was no warning before the failure

NHTSA ID

11711924

Incident

Dec 5, 2025

The contact owns a 2018 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle was shaking abnormally. No warning light was illuminated. The vehicle was taken to the dealer to be diagnosed, and it was determined that the engine needed to be replaced. The vehicle was then taken to an independent mechanic, who determined that the torque converter had failed. The torque converter was replaced, but the failure persisted. The vehicle was taken back to the independent mechanic, who replaced the torque converter a second time. The manufacturer was not made aware of the failure. The failure mileage was approximately 140,000.

NHTSA ID

11711245

Incident

Jan 8, 2026

Mileage

140,000 mi

Engine failure. 6.2l with AFM system Extreme oil consumption Heavy metal in oil Loud ticking 120789 miles Purchase date 05/29/2025 Madras, Oregon Chevrolet Dealer

NHTSA ID

11709032

Incident

Oct 29, 2025

The contact owns a 2018 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the air conditioning system became inoperable. There was no warning light illuminated. The contact stated that the air conditioning system failed to function properly. The vehicle was taken to an independent mechanic, where it was diagnosed, and determined that the air conditioning condenser had failed and needed to be replaced. The vehicle was not repaired. The dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The failure mileage was not available.

NHTSA ID

11705563

Incident

Dec 17, 2025

I have 125,000 miles on my truck. I was traveling with my grandkids in the back seat. We were going through a four way stop. My truck started tapping like a lifter issue. The next thing I know is the truck engine light started flashing and car started to shake. Then, my truck lost all power and a big cloud of blue smoke came out of the tail pipe. The truck could not be driven any further. The symptoms: engine tapping, low oil, engine light flashing, shaking, lost all movement, and a cloud of smoke We had to tow my truck to the dealer and they are still accessing the issue. All symptoms are identical to the current recall of the GMC engines.

NHTSA ID

11705013

Incident

Dec 10, 2025

The injector failure in my 2018 GMC Sierra 1500 resulted in repeated misfire conditions (P0300 and P0307), causing the vehicle to lose power unexpectedly while driving. The engine would hesitate, shake, and struggle to accelerate, especially during merging or highway speeds. These symptoms created a significant safety hazard because the vehicle could not reliably maintain speed or respond to throttle input. Sudden power loss in traffic exposes the driver and surrounding motorists to an increased risk of collision, particularly during lane changes, freeway merging, intersection crossings, and passing maneuvers. The dealership confirmed internal injector failure, and the vehicle has been out of service for three months without resolution. This is a safety-critical defect that compromises vehicle controllability, stability, and safe operation on public roads.”

NHTSA ID

11700630

Incident

Nov 19, 2025

2018 GMC Sierra started having shuddering/jerking/jumping problems at around 60k miles. This problem occurs while driving on straight aways, going uphill and while in drive at a stop sign/light. When the gas is accelerated the truck then hesitates and jerks/jumps. We have taken it to the GMC dealership and paid for the diagnostics and were informed “the problem wasn’t severe enough”. The truck has only been serviced by GMC dealership. So after failed attempts with GMC service department we have taken it to a local small auto shop and they automatically said it was the Drive Train and needed to be taken to a transmission shop. We have been GM owners for decades and are so disappointed in the service received from them.

NHTSA ID

11700188

Incident

Nov 18, 2025

The contact owns a 2018 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the transmission vibrated. No warning lights were illuminated. The vehicle was taken to an independent mechanic, where it was diagnosed with a failing torque converter. The contact was informed that the torque converter needed to be replaced. The vehicle was not repaired. In addition, the contact was informed of a Manufacturer's warranty. The contact was informed of a Manufacturer's warranty for the 2018 GMC vehicle's transmission failure due to the incorrect oil being used during production of the torque converter. The dealer was made aware of the failure; however, the contact was informed that the manufacturer needed to approve the repair coverage. The manufacturer was made aware of the failure but provided no assistance. The contact was advised to contact the NHTSA Hotline to report the failure. The failure mileage was approximately 89,000.

NHTSA ID

11699411

Incident

Nov 7, 2025

Mileage

89,000 mi