GMC Sierra Complaints (2018)
371 consumer complaints on file.
- #11696714October 31, 2025ENGINE, SEATS, POWER TRAIN
I purchased a 2018 GMC Sierra 1500 6.2 Denali new. I followed all service requirements including oil changes by GM dealerships. 2025 i noticed my truck power was decreasing. Than I started to hear knocking noses. I took it to a dealership for diagnosis but they couldn't identify anything. Finally it started to skip this is when a dealership diagnose it as being an issue with the active fuel management system. They said my lifters, camshaft, and various other parts was damaged and had to be replaced. Additionally, they said it was a recall on 6.2 engines with the same identical issue but my year wasn't included. The cost to repair approximately 10,000. I really need your attention to this matter! September 10, 2025 my truck placed me and others in danger when it lose engine power. Also my engine light was on for the first time.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11692321October 9, 2025ENGINE AND ENGINE COOLING
The contact owns a 2018 GMC Sierra 1500. The contact stated that while attempting to accelerate from a stoplight, the vehicle hesitated before accelerating. A day later, the failure reoccurred, and the RPMs increased before the vehicle accelerated. There were no warning lights illuminated. The vehicle was taken to the dealer, who diagnosed that the connecting rod had failed, and there were metal shavings inside the engine. The contact was informed that the engine needed to be replaced. The contact related the failure to NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the VIN was not included. The vehicle was not repaired. The manufacturer was informed of the failure and confirmed that there was no recall on the VIN. The manufacturer opened a case for the failure. The manufacturer referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 169,000.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11691158October 3, 2025ELECTRICAL SYSTEM:INSTRUMENT PANEL:SPEEDOMETER/ODOMETER
Odometer Fraud. The contact purchased a 2018 GMC Sierra 1500. The contact discovered that there was a mileage discrepancy after the purchase. The vehicle was a private sale. At the time of purchase, the vehicle mileage was 72,000. It was later discovered later that the mileage was 241,556.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11683980August 29, 2025POWER TRAIN
Transmission shutters when going over 50mph
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11682446August 22, 2025POWER TRAIN
The contact owns a 2018 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed toward the residence, the accelerator pedal was depressed and traveled to the floorboard, and the vehicle failed to drive forward as intended. The vehicle started rolling backwards and the contact carefully maneuvered the vehicle while attempting to park. There was no warning light illuminated. The vehicle was towed to the dealer and diagnosed with transmission failure. The contact was informed that the transmission needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 101,000.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11681723August 19, 2025ENGINE
The contact owns a 2018 GMC Sierra 1500. The contact stated that while driving on a neighborhood road at 40 MPH, the check engine warning light was flashing with an abnormal knocking sound coming from the engine, and the vehicle was vibrating abnormally. The contact pulled over and used a diagnostic scanner to perform a diagnostic test on the vehicle. The scanner retrieved DTC: P0301 (Cylinder #1 Misfire). The vehicle was towed to a local dealer to be diagnosed, and the contact was informed that the lifters, pushrods, camshaft, sparkplugs, and oil pump were faulty and needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The approximate failure mileage was 111,000.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11680036August 12, 2025POWER TRAIN
Transmission shutting and torque converter came apart destroying the transmission.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11680155August 12, 2025UNKNOWN OR OTHER
The truck started to vibrate or shudder . We are having to deal with replacing the transmission on our truck, which has only 45,000 miles on it. We have noticed numerous complaints about transmission problems with this model and the place that is replacing the transmission said they have had 3 customers in the last couple of months with the same issue on the same GMC model. This is a lot for our small town and area. Why hasn't GMC issued recalls ?
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11679813August 11, 2025ENGINE AND ENGINE COOLING
The contact owns a 2018 GMC Sierra 1500. The contact stated that while driving at various speeds, there was an abnormal banging sound coming from the vehicle. There was no warning light illuminated. The contact inspected fluids but found no defects with the vehicle. The vehicle was then taken to an independent mechanic, where the mechanic discovered that the lifters and cam shaft were defective. Due to the failure, the engine was replaced. The contact stated that recently, the abnormal tapping sound returned. The vehicle was taken back to the independent mechanic, who confirmed that the failure with the lifters had returned. The vehicle was taken to a dealer who confirmed the lifter failure, and the contact was provided an estimate for the repair. The manufacturer was notified of the failure, and the contact was provided a case number. The contact was then referred to the NHTSA to report the failure. The vehicle was not yet repaired. The failure mileage was approximately 90,000.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11678969August 7, 2025ENGINE
Radiator cracked along outer edges. Similar to previous TSB’s as released by GM, but my vehicle doesn’t fall under the years covered by that TSB
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11678809August 6, 2025ELECTRICAL SYSTEM, ENGINE, STEERING
2018 GMC Sierra SLT's electric power steering suddenly stopped working, I almost got killed this issue has been reported by other owners
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11678591August 5, 2025ELECTRICAL SYSTEM
The contact owns a 2018 GMC Sierra 1500. The contact stated that the battery had been replaced three times since 2018. The vehicle was taken to the dealer; however, the failure was not duplicated. The contact referenced an unknown recall; however, the VIN was not associated with the recall. In addition, the contact stated that the first battery was replaced a month after the vehicle was purchased, and the second battery was replaced three weeks after the first replacement. The contact stated that the third battery was replaced a day after the second battery replacement. The manufacturer was made aware of the failure and a case was filed. The contact was advised to contact the NHTSA Hotline to report the failure. The failure mileage was approximately 36,000.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11676398July 26, 2025POWER TRAIN
I have a 6.2 engine that had a number 4 cylinder failure due to a engine defect of the crankshaft. They have recalled the 6.2 motors on the 2021-2024 year models. The 2018 year models with the 6.2 engine should be recalled also bc they are having the same issue. Please help
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11676175July 25, 2025POWER TRAIN
The contact owns a 2018 GMC Sierra 1500. The contact stated while driving approximately 70 MPH and attempting the pass another vehicle, the accelerator pedal was depressed; however, the vehicle lost motive power and decelerated unintendedly. The contact pulled over and restarted the vehicle however, the vehicle failed to accelerate above 40 MPH. The vehicle was later taken to the local dealer who diagnosed that the transmission was faulty and needed to be replaced. The vehicle was not repaired. The manufacturer was not yet contacted. The failure mileage was 81,000.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11675936July 24, 2025POWER TRAIN
The contact owns a 2018 GMC Sierra 1500. The contact stated that while driving at 60 MPH, there was an abnormal vibration coming from the steering wheel. No warning light was illuminated. A dealer was contacted. The vehicle was taken to the dealer, where it was diagnosed, and determined that the transmission needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure and transferred the contact to the NHTSA Hotline to report the failure. The approximate failure mileage was 125,326.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11675477July 22, 2025EQUIPMENT:ELECTRICAL:NAVIGATIONAL SYSTEM(GLOBAL POSITIONING SYSTEM)
The embedded navigation system in my 2018 GMC Sierra is no longer supported. Paid map updates were available until 2023, when General Motors discontinued them without notice. This system was marketed as a core feature and provided offline GPS guidance independent of cell reception. I discovered the change while attempting to purchase an update and was told there are no remaining copies and that no further updates will ever be made. I was never notified. When I contacted support, I was transferred through six departments. One representative admitted that customers were supposed to be informed but were not. She stated they are trained to say “there’s nothing we can do” and acknowledged receiving hundreds of similar complaints. She also confirmed the final map update existed but was allowed to sell out. This puts safety at risk, particularly for drivers in rural areas, areas with poor cell service, or while towing. The system is not CarPlay-based and does not rely on mobile data. It was the only in-vehicle routing system many drivers depended on during travel, including emergencies. Its quiet discontinuation means drivers no longer have access to accurate, integrated navigation—reducing their ability to safely plan or adjust routes while on the road. The failure to maintain this system or provide reasonable access to the final update undermines long-term vehicle safety and owner trust. General Motors has not offered an inspection, recovery, or remedy.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11674727July 19, 2025ENGINE, POWER TRAIN, FUEL/PROPULSION SYSTEM
I own a $35,000 2018 gmc Sierra 1500 6.2l V8 4x4 Denali, which is currently down due to engine failure while I was driving down the road.. never had a check engine light on the dash. Haven't had the truck a year before it quit. Rods knocking, crankshaft bearings, loss of power, high rpm with little acceleration. I could have the peddle down to the floor and would barely get to 20 mph.. the motor would jump so bad, you would think it's going to jump out the truck. I have replaced several parts on the truck, including oil pump, filter, solenoid valve sensor, fuel pump, injectors, and sensors, battery, starter a couple times. Did all that replacing for it to get worse and finally quit while driving.. I was stranded in the middle of the road.. IV reported it to the Recall people, but nothing helped. I have taken my vehicle to Express Chevrolet and they did a diagnostic test, which I provided the list they gave me below. When I took it to them, I was using Endurance Warranty, but they denied my claim due to the issues and they didn't cover them. At the time, the motor was still jumping, but smoke was coming out the tailpipe extremely bad, the truck was jerking and jumping. After replacing everything I listed, the truck got worse, started screeching and knocking loudly, loss of engine power, little acceleration. The day the motor quit on me while driving, I got the mph up to about 55-60 and it just quit, and hasn't started back since.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11674096July 16, 2025ENGINE
The contact owns a 2018 GMC Sierra 1500. The contact stated while his mother was driving 75 MPH on the highway, there was a popping and ticking sound coming from the engine, and while depressing the accelerator pedal the vehicle failed to respond. The driver was able to pull over to the right side of the road and waited for tow truck assistance. A dealer was not contacted. The vehicle was towed the dealer and was diagnosed and determined that the engine needed to be replaced. The vehicle was repaired. The manufacturer was notified of the failure, and informed the contact engine would take a while to be ordered. The contact was referred to the NHTSA Hotline for assistance. The failure mileage was 58,000.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11671301July 5, 2025POWER TRAIN
I'm experiencing constant transmission shuddering at constant speed between 25 and 40 mph. This is a know issue, General Motors known issue, with the 8 speed transmission installed in this vehicle. TSB 18-NA-355 was issued in August of 2019 for this issue, but general motors refuses to recall all affected vehicles. Something needs to be done about this!
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0
- #11670689July 2, 2025ENGINE, POWER TRAIN
This 2018 GMC Sierra has 100,000 miles on it and in April 2025 the transmission went out and needed a new one. Now in July 2025 the engine has lifter failure leading to the need of a new engine.
- Crash:
- No
- Fire:
- No
- Injuries:
- 0
- Deaths:
- 0