2018 GMC Sierra 1500

DRIVING 70 MPH ON [XXX] IN MODERATE TRAFFIC WHEN MY VEHICLE SUDDENLY SLOWED DRAMATICALLY AND BEGAN TO SHUDDER . I WAS IN THE MIDDLE LANE OF THREE WESTBOUND MARKED LANES AND WAS ALMOST HIT BY A DRIVER BEHIND ME WHICH HAD BEEN FOLLOWING TOO CLOSELY. THE CHECK ENGINE AND TRACTION CONTROL LIGHT CAME ON AND MY OIL GAUGE WENT TO THE HIGH SIDE. I EXITED ONTO [XXX] AND AT 40 MPH THE TRUCK WOULD SHAKE AND SHUDDER UNTIL I DROVE THE 6 MILES TO MY RESIDENCE. ON [XXX], I HAD THE VEHICLE TOWED TO LASH GMC DEALERSHIP IN JOHNSTOWN OHIO. ONCE THERE THE VEHICLE WAS DIAGNOSED WITH A FAILED LIFTER THAT BROKE INTO PIECES RESULTING IN A BENT ROD AND DAMAGED CAM SHAFT. THE DEALER RECOMMENDED FULL ENGINE REPLACEMENT DUE THE SEVERITY OF THE FAILURE. THE TRUCK IS A 2018 GMC SIERRA DENALI WITH ONLY 65,449 MILES ON IT. IT COST ALMOST $70,000.00 NEW AND THE REPLACEMENT ENGINE COST ME $14,221.96. I FEEL MY PERSONAL SAFETY WAS JEOPARDIZED IN THIS INCIDENT. SINCE THAT TIME I HAVE RESEARCHED THE 6.2 GMC ENGINE ONLINE AND HAVE FOUND REPORTS OF NUMEROUS SIMILIAR FAILURES AND INCIDENTS INVOLVING THE ENGINE IN QUESTION. I TRULY FEEL NHTSA SHOULD TAKE A STRONG LOOK AT THE ENGINE FAILURES INVOLVING THIS ENGINE AND FORCE GMC TO REPAIR OR REPLACE THE ENGINES IN QUESTION DUE TO THE SAFETY ISSUES INVOLVING THE ENGINES FAILURES IN TRAFFIC AND THE RISK ASSOCIATED WITH AN OCCURENCE. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

I have a 2018 GMC Sierra 1500 with a 6.2 motor. Back in December of 2024, I had to replace a tie rod, cam shaft, and the lifters. $8400 to get everything replaced. Since my warranty had expired, I had to pay all of this out of pocket. I know there is currently an investigation going on in GMC's 6.2 motors. Almost 900,000 engine failures. This is unacceptable. GMC just needs to man up and send out the recall notice. Since I have already had to pay for my replacements, GMC should do the right thing and and cut me a check.

The failure was a lifter collapsed in my vehicle's motor. I had reduced power and major shuttering due to the issue. If I had been towing a load I would have possibly become a hazard by not maintaining a speed that would have been able to keep up with traffic flow. Also if I had been in an congested traffic area I would have been slower to clear or have major breakdown causing increased backups. It was confirmed by a local shop. There were no warning lights at the time of incident, nor leading up to this incident. Fortunately no accidents or disruptions happened and I had to be towed in to a repair shop.

My 2018 Silverado 1500 has had 3 cylinder 4 misfires over a 9 month period that had to be repaired after warranty. This caused the repair/replacement of the lifters. I have had this happen for a forth time this year January 7 2025 with the same code of "cylinder 4 misfire". That means four of the same issues in one year. I can be driving along smoothly, then suddenly from one light to the next, the check engine light comes on with the misfire to cylinder 4 coming on. It was shared with me the AFM can cause this to happen. On the third time of misfire, I saw a little smoke, then once it was repaired with lifters replaced, no smoke and back to running smoothly. This time the intake cam lobe was scored which voided the warranty. I am now at a crossroad as to what to do now, and have parked the truck for now. It is my understanding the 5.3L engine was considered a solid engine until the AFM was installed. Did I mention this is the first "truck" I have ever owned? I have had a Chevrolet vehicle since I was able to drive, and have never had engine problems of this magnitude. My concern now is that this could cause my engine to lock up while I'm driving around and cause a possible accident. I depend on this truck as my mode of transportation, but now I have to make a decision that impacts me greatly as a senior citizen on a fixed income.

The contact owns a 2018 GMC Sierra 1500. The contact stated that while driving on the highway at various speeds, the vehicle occasionally shuts off. The contact stated that several unknown warning lights were illuminated. The contact stated that the vehicle was pulled over to the side of the road and restarted. The contact was able to continue driving. The vehicle was taken to a local dealer and was diagnosed; however, the cause of the failure was not found. The contact was informed to take the vehicle back to the dealer if the failure returned. The manufacturer was notified of the failure. The approximate failure mileage was 128,000.

This vehicle has 88400 miles, it out of warranty, which I know this, I use AMSOIL ASM SIG SERIES SYN SAE 0W-20 , 5.3L GAS. TWO YEARS AGO, I CHANGED OIL AT RICHARD BUICK GMC IN DAYTON, OH AND SENT A SAMPLE OF THE OIL TO OIL ANALYZERS FOR AN ANALYSIS, THEY SET IT BACK, IT SHOWED THERE WAS A LEVEL 4 SEVERE GASOLINE IN THE OIL. THEY CHANGED THE HIGH SPEEP FULE PUMP, BOTH IN JECTORS, AND IT THOUGHT IT WAS FIXED, ON 12 - 11 -24 HAD THE OIL CHANGED AT LOCAL BOYS SERVICE CENTER, SENT A SAMPLE OF THE OIL-TO-OIL ANALYZERS AND RECIEVED BACK, A SEVERE FUEL LEAK OF GASOLINE IN THE OIL, i DON'T THINK THAT MANY DRIVERS WHO HAVE THIS VEHICLE KNOW ABOUT THIS DANGEROUS PROBLEM, IT COULD CAUSE AN ENGINE FAILURE OR EVEN WORSE, GENERAL MOTORS NEEDS TO FIX THIS PERBLEM.

Vehicle is a 2018 GMC Sierra Crewcab 4x4 with a 5.3 engine. The vehicle was purchased new in Washington and serviced at the Chevrolet dealership in Oregon within vehicle recommended service intervals. At 64K miles, the engine developed a sudden AFM lifter issue. Lifter for cylinder #6 came apart causing the engine to miss, smoke, have excessive oil on the spark plug, and low cylinder PSI (75 compared to others at 200+). Vehicle is just outside of it's 5 yr/60K powertrain warranty. Vehicle is undrivable and will need probable engine replacement due to damage from AFM lifter failure. My mechanic verified the miss, oil on the spark plug, and low PSI. The local Chevy dealership removed the valve cover, inspected, and advised that the lifter came apart. Dealership wants $1200 to pull the head to determine extent of damage and $4-5K to repair valves or $12-14K for engine replacement. GM offers no assistance at this point.