84 of the 928 complaints about the 2015 GMC Sierra 1500 are about the engine — 9% of everything reported for this model year. Half of the failures with a mileage on record happened before 56,000 miles.
84
Complaints
1
Crashes
2
Fires
0
Injuries
Filed with NHTSA, in their own words.
ENGINE
Active Fuel Management Miss firing Idle rough Shaking Loss of power #7 cylinder loss of all compression Bad fuel mileage Skipping
NHTSA complaint #11732442 — an unverified report by a vehicle owner.
ENGINE
The contact owns a 2015 GMC Sierra 1500. The contact stated that while driving at approximately 45 mph, he observed a popping noise beneath him. The contact stopped the vehicle and observed smoke emanating from the front of the vehicle. The vehicle went into limp mode, lost power, and when the brake was depressed, the vehicle did not slow the vehicle down as intended. The contact stated that as he pulled into a parking lot to inspect the vehicle, he observed flames emanating from the hood. The contact stated that he pressed the hood latch, which did not open the hood, and he then exited the vehicle and observed the hood engulfed in flames. The contact mentioned that a store employee brought a fire extinguisher out and attempted to extinguish the flames. The fire department was called and extinguished the fire fully. There was no police report, but the police did come out to assist. The contact sustained a right-hand injury, but medical attention was not needed. The vehicle was then towed to the residence. The vehicle was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was 124,000.
NHTSA complaint #11724912 — an unverified report by a vehicle owner.
ENGINE
Another GM truck AFM failing. It failed at 70,000 miles causing P0307 cylinder 7 misfire. No aggressive driving just commuting to work. Truck just got done with a new oil change. It's another to add to the hundreds/thousands seen on Reddit threads of all 5.3/6.2 AFM/DFM that this organization turns a blind eye to.
NHTSA complaint #11722758 — an unverified report by a vehicle owner.
ENGINE
The engine seized up traveling about 40MPH in the middle lane on a busy road with my child in the passenger seat. I was able to get off the busy road but part of my truck was still intruding into the lane. The truck is parked at my house. The vehicle has not been inspected by anyone and is still in the same condition as the day the engine seized. The only thing that indicted any issue was a couple popping noises right before the engine seized. It all happened while I was driving in traffic and I did not notice any indications on dash. I was more concerned about getting off the road and out of traffic before I got rear-ended or involved in a pile up.
NHTSA complaint #11712775 — an unverified report by a vehicle owner.
ENGINE
The GMC Sierra 1500 started a knocking sound. The collapsed lifter on a AFM cylinder bent a push rod which led to cam failure. Metal fragments are throughout the oil system.
NHTSA complaint #11703847 — an unverified report by a vehicle owner.
ENGINE
While driving the vehicle at approximately 40MPH the motor made a tapping sound, I was able to pull into a parking lot and have the vehicle towed to the dealer. The dealer told me that the vehicle was out of warranty and appeared that under initial inspection the would have to rebuild the motor due to a lifter failure at the estimated cost of $18,000. I had the vehicle towed to a reputable repair shop and after the did a tear down to the small block they determined a bent push rod and broken lifter, all pushrods and AFM lifters were replaced at the cost of $10,754. dollars as invoice shows. The issue occurred again on 10/25/25 causing catastrophic failure that will cost me a complete engine replacement.
NHTSA complaint #11696998 — an unverified report by a vehicle owner.
ENGINE
This occurred 5+ years ago. Coming home one night I had a sudden loss of power with the truck and barely made it home. Was able to limp the truck to the dealership the next day and was told that one side of the engines lifters had failed. Prior to the failure I had noticed a ticking sound coming from the engine that was becoming increasingly more prominent. It was several thousand dollars to repair. Fortunately the failure occurred near home, not on the freeway where I could have been dodging cars while trying to limp the truck to the shoulder. Some online research while the repair was being done revealed that several other owners with the 6.2L engine had the same problem. When I mentioned it to the dealer the response was that they had no bulletins from GM on the issue and I was stuck with the bill. Got the same response a year or two later when the torque converter on the transmission went out. The reason I am reporting it now is I saw that GM is recalling 6.2L vehicles with lifter issues but not back to 2015 even though the issue appears to go back farther than that. They claim it's limited to a specific run of engines for the recall. They have been having various lifter problems for many years that have put drivers in danger when they fail but refuse to acknowledge it. As for the repair they made to the engine I've driven another 70 K miles and the ticking has started again. I fear another failure. Please note that the date previously given for the incident is my best guess.
NHTSA complaint #11696869 — an unverified report by a vehicle owner.
ENGINE
Lifter and camshaft failed
NHTSA complaint #11693130 — an unverified report by a vehicle owner.
ENGINE
I have owned 4 of these trucks in my lifetime ranging from 2007-2015 all equipped with the same drivetrain. 5.3l engine and 6l80 transmissions. All have had the same failures. The engine afm system particularly the lifters fail which in turn destroys the camshaft and destroys the engine. More importantly the transmission torque converter fails sending debris through the whole system causing a sudden loss of drive. This happened while driving down the road and was a safety concern for myself and others. This time it costed me $6500 to replace the transmission. All of the trucks I have owned experianced the same failures how is this not a problem?
NHTSA complaint #11681851 — an unverified report by a vehicle owner.
ENGINE
At low speeds when applying the brake, whether in a turn or traffic, the vehicle will shut off completely. This has happened multiple times and has almost caused accidents on a few occasions. It has also happened while just driving down the road, the entire truck lost power and then came back, the windshield wipers came on as well.
NHTSA complaint #11674013 — an unverified report by a vehicle owner.
ENGINE
With all the GM engine problems being recalled, the known issue witht he AFM/DOD on all the models 2013 and up on 5.3L and 6.2L engines should have been recalled. The valves are known to collapse and nending push rods, causing damage to the cam shaft. This can cause ht eengine not to run. The symptoms and possible icidents include the same as the current recall NHTSA Campaign Number: 25V274000. My engine has been repaired twice now due to this AFM/DOD issue. I have all the paperwork from GM dealer that repaired it. I will upload the first repair, I need to scan the second repair. The engine is now making the ticking valve sound ans the vehicle is services regularly. What component or system failed or malfunctioned, and is it available for inspection upon request? AFM/DOD valves collapse causing enegine damage. How was your safety or the safety of others put at risk? Lack of power while driving, loud engine knock Has the problem been reproduced or confirmed by a dealer or independent service center? Yes, by the dealer Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Insepcted by the dealer, and only the damaged parts replaced, not all the valves that can still collapse. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? No warning, engine light came on due to misfire on both incidents.
NHTSA complaint #11658005 — an unverified report by a vehicle owner.
ENGINE
The contact owns a 2015 GMC Sierra 1500. The contact stated while driving approximately 50 MPH, the vehicle started to lose motive power and then stalled. The contact stated that there was a black cloud of smoke coming from the exhaust pipe. The check engine warning light was illuminated. The contact had the vehicle towed to an independent mechanic. The vehicle was diagnosed, and it was determined that the rod bearings had failed and needed to be replaced. The vehicle was not yet repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 122,000.
NHTSA complaint #11657524 — an unverified report by a vehicle owner.
ENGINE
The contact owns a 2015 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle stalled with the check engine warning light illuminated. The vehicle was able to be restarted. The vehicle was taken to an independent mechanic, where it was diagnosed that the engine had failed and needed to be replaced. The vehicle was not repaired. The vehicle was taken to the dealer, where the diagnostic result was confirmed. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 97,000.
NHTSA complaint #11657568 — an unverified report by a vehicle owner.
ENGINE
The contact owns a 2015 GMC Sierra 1500. The contact stated that while the vehicle was parked and occupied at the residence, the contact exited the vehicle and went inside his home; however, forty minutes later, while attempting to start the vehicle, the vehicle failed to respond as needed. The contact stated that a bystander inspected the vehicle and assumed the starter had failed. No warning light was illuminated. The vehicle was towed to the dealer, where it was diagnosed and determined that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure and suggested that the contact take the vehicle to the local dealer for assistance. The approximate failure mileage was 141,000.
NHTSA complaint #11654944 — an unverified report by a vehicle owner.
ENGINE
Motor blew up while driving down the road. Had to replace motor on 08/23/2023 at about 116,000 miles. Left me and my family stranded in the middle of no where. Was going around 60 miles an hour and when passing someone got up to 71 mph and then motor blown push rod bent. Transmission issues. Hesitation when switching from park to drive/ reverse. Takes at least 40 seconds and when you accelerate it will jerk so hard. Will lunge forward very sudden and sometimes even when coming to a stop at a stop sign. This happens almost every day.
NHTSA complaint #11648678 — an unverified report by a vehicle owner.
ENGINE
In the fall of 2023 my 6.2L V8 with only 107,565 well maintained Miles completely seized up and shut off without any warning lights or other indications of failure. I was going up a steep hill and luckily I was able to get to the side of the road by coasting backwards to a stop and fortunately no one else behind me at the time. I did not get my truck back until late spring of 2024. I paid over $13k out of pocket to replace the engine because of this issue that is known to many other GM truck owners. Prior to catastrophic engine failure I’ve had multiple services including replacement of torque converters which would cause the truck to shake violently when shifting along with violent shifts in the 8 speed transmission and at times the feeling of being rear ended when slowing down or coming to a stop which GM claims to be “normal operation”. The engine failure was never investigated by any other parties but was looked at by the dealership service department. Both violent shifts and torque converter shutter were also confirmed by the dealer but only fixed with what I consider to be temporary remedies.
NHTSA complaint #11646409 — an unverified report by a vehicle owner.
ENGINE
There is a known defect by other consumers with the same year/make/model as mine that causes the radiator to leak. I replaced the original radiator about a year ago with a new GM radiator (84207654) and it’s now leaking as well.
NHTSA complaint #11644265 — an unverified report by a vehicle owner.
ENGINE
Purchased this vehicle on 06/29/2023 from Robideaux Motors in Coeur d Alene ID. with 81,397 mile on the odometer. On 01/05/2024 the 6.2L engine with 84,109 miles, started having a ticking sound after starting it at my son's house two miles from home. I called the dealer and was told to bring it in for diagnosis by a tech. While driving the truck to the dealer the ticking got worse and motor started to shudder and the check engine light came on. Cause was a misfire on cylinder 4 due to bent push rod and failed lifter. Replaced lifter bank 2 with new push rod. Total cost was $2,852.74 (have invoice). After many calls and letters to my extended warranty company, they finally paid $1688.54 of the total cost. On 08/29/2024 the same ticking sound started again as well as the shudder and check engine light. I had it towed back to Robideaux Motors and was told it was a misfire on cylinder 6 due to lifter failure. Robideaux Motors did repair under their repair warranty. I know that this vehicle is not included in class action suit, due to the year. I feel this to be a continuing problem with the GM 6.2 and 5.3L motors encompassing many model years. Just wanted to document that the number of years covered in the law suit should be expanded.
NHTSA complaint #11640994 — an unverified report by a vehicle owner.
ENGINE
Truck is equipped with AFM and the lifters failed causing a no -power situation. First happens at 57,000 miles then again at 82,000 miles. Not only was this a dangerous situation, but also a very expensive situation. GM knows these are defective and should have been recalled and repaired on their dime, not mine. Pictures of bill included are only of the first repair. Second repair pictures are available upon request.
NHTSA complaint #11638850 — an unverified report by a vehicle owner.
ENGINE
Lifter failure cylinder 1 at 82458 should be a recall
NHTSA complaint #11627668 — an unverified report by a vehicle owner.
ENGINE
The motor goes into a V4 to v6 to v8 Mode on its own .. in which it makes the lifters & pistons change to cause problems with the motor
NHTSA complaint #11619273 — an unverified report by a vehicle owner.
ENGINE
Had to have transmission replaced and engine work (lifters and cam) on a GM truck with 100,000 miles on it. Cost $8,000. Was told by both mechanics that they've seen many of this same issue with this same year truck for GM.
NHTSA complaint #11615649 — an unverified report by a vehicle owner.
ENGINE
Had two lifters collapse and fail. Replaced transmission twice due to torque converter failure
NHTSA complaint #11589780 — an unverified report by a vehicle owner.
ENGINE
The contact owns a 2015 GMC Sierra 1500. The contact stated while his daughter was driving approximately 25 MPH, the vehicle started vibrating violently. The contact stated that his daughter reported seeing several unknown warning lights illuminated. The vehicle was stopped and towed to a dealer. The dealer diagnosed and determined that the rod bearings were damaged and caused damages to the lifters. The contact was informed that the rod bearings and lifters needed to be replaced. The vehicle was not repaired. The manufacturer was informed of the failure. The contact researched online and related the failure to Technical Service Bulletin: 20-NA-038 (Engine). The failure mileage was approximately 43,000.
NHTSA complaint #11569555 — an unverified report by a vehicle owner.
ENGINE
I would like to bring to your attention an alarming incident that occurred on January 3, 2024, with my truck. While accelerating onto the highway, the engine and drivetrain failed suddenly, posing a significant safety risk. The failure left the engine incapable of functioning properly, which could have resulted in a catastrophic accident. Seeking answers about the cause of this dangerous malfunction, I promptly arranged for an inspection by RNZ Concepts. After evaluation, they suspected a potential problem with the hydraulic lifter or camshaft. It is baffling to note that, other than an initial transmission replacement, there were no further indications of any underlying issues, as the truck is regularly serviced. Additionally, within 60 days of purchasing the vehicle, similar issues arose, requiring additional repairs that were paid out-of-pocket at the time. Now, the vehicle is once again out of commission due to persistent GMC failures. The estimated repair cost is expected to be between $6,000 and $10,000.
NHTSA complaint #11565013 — an unverified report by a vehicle owner.
ENGINE
Rainy road, 60mph on the hw with my family. Truck decides to engage stabilitrak or something to that feel and locked up the brakes. Talk about a scary moment with an 18 wheeler coming in hot behind you. Obviously, in the moment, I had no clue what was happening other than something with the truck was malfunctioning. This scenario could have gone wrong in so many ways. I'm honestly in shock someone has not been killed because of this?
NHTSA complaint #11559861 — an unverified report by a vehicle owner.
ENGINE
The contact owns a 2015 GMC Sierra 1500. The contact stated that while driving approximately 60 MPH and hauling a boat, the vehicle started operating at reduced power. There were no warning lights illuminated. The vehicle was taken to an independent mechanic and the contact was informed that the push rods were bent, and the lifter had collapsed. The contact called the local dealer, but the vehicle was not diagnosed or repaired. The manufacturer was contacted and referred the contact to the dealer. The failure mileage was approximately 90,000.
NHTSA complaint #11537229 — an unverified report by a vehicle owner.
ENGINE
The body has rust coming through on the lower body panels by the rear doors of a crew cab. Have to replace the AC condenser on a 2015 gmc Denali. Looks like GMC already knows there is an issues with this, but no recall on the 6.2L sierra denalis.
NHTSA complaint #11522004 — an unverified report by a vehicle owner.
ENGINE
Truck loses power engine dies while driving after turning at slow speeds. Engine will restart after a few minutes like it never happened does not show any DTC codes or check engine lights. It is intermittent with no advance notice very dangerous to drive. Seems to be a common problem for all GM trucks and SUVS from 2014 - 2017
NHTSA complaint #11515701 — an unverified report by a vehicle owner.
ENGINE
Improper cooling cycles causing coolant leaks on the radiator
NHTSA complaint #11490566 — an unverified report by a vehicle owner.