2019 GMC SIERRA 1500 Complaints

I own a 2019 GMC Sierra 1500 Denali equipped with the 6.2L L87 engine. On or around December 31, 2025, the vehicle developed a loud knocking noise from the engine that became worse with RPM increase. The truck was taken to a GMC dealership for diagnosis and repair under warranty/service contract coverage. The dealership initially diagnosed valvetrain-related failure and replaced multiple top-end components including lifters, rocker arms, camshaft-related parts, belts, pulleys, hoses, and associated hardware. After reassembly, the engine reportedly started briefly and then failed again. The dealership then performed additional teardown and determined the lower end of the engine had also failed. I was informed by dealership staff that rod bearing failure is “very common” on the L87 6.2L engines. Due to the extent of the damage, the vehicle ultimately required a complete long block replacement. My truck remained out of service from approximately 12/31/2025 until 5/1/2026, a period of roughly four months. During that time, there were repeated delays involving diagnosis, inspections, warranty approvals, and additional teardown procedures. The vehicle had approximately 111,858 miles at the time of failure and had been regularly maintained. Prior to the engine failure, the truck exhibited abnormal engine ticking/knocking noises under load and higher RPM operation. The final repair performed was replacement of the engine long block assembly. I am submitting this report because the dealership indicated this type of lower-end/rod bearing failure is common on the GM 6.2L L87 platform, and I believe this issue may represent a broader reliability and safety concern affecting other owners.

On March 14 2026 i was driving from [XXX] . To [XXX] to have my tires checked because i felt a strong vibration on my steering column and truck itself, it was getting worse so i took it to my mechanic who does my regular maintenance on truck. After inspecting tire ( [XXX] 55 R20) was called over and shown that my front passenger side tire had a flat spot, it looked deformed mechanic informed me that the tire had separated from radial. And i need to get another tire right away, since there was non in stock we did the next best thing we took the front passenger tire the affected tire put it in the back and put the rear good tire up front. The next day i was on my way to purchase the replacement tire when the tire blew out. I was on a heavily traffic road [XXX] . I managed to take control of truck doing about 40 mph at the time and drove it off the road to a safer spot to look at damage. Well the passenger rear tire witch was originally on the front that had the separated radial blew a chunk out of the inner sidewall. I put on the spare and went and replaced the tire with another goodyear new tire. On march 28 as i was coming home from [XXX] late at night the driver side rear tire blew as well again had to put on spare and next day took to local mechanics in [XXX] , and checked tire and again i was told that the tire separated from radial and that was the cause of blew out, they inspected all the tires at this point since this was the second tire from the same DOT set with less then 12000 miles that had separated. Well they found a third tire that had aldo separated and had a flat spot on driver side front tire, now there are 3 tires from the same set, coincidence, i dont think so i replaced the second and third tire. One the third day April 1, 2026 the passenger side front tire blew as well, now i have 4 tires that had radial separation with less then 12000 miles and less then a year old, in a mater of a month. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

On March 14 2026 i was driving from [XXX] . To [XXX] to have my tires checked because i felt a strong vibration on my steering column and truck itself, it was getting worse so i took it to my mechanic who does my regular maintenance on truck. After inspecting tire ( [XXX] 55 R20) was called over and shown that my front passenger side tire had a flat spot, it looked deformed mechanic informed me that the tire had separated from radial. And i need to get another tire right away, since there was non in stock we did the next best thing we took the front passenger tire the affected tire put it in the back and put the rear good tire up front. The next day i was on my way to purchase the replacement tire when the tire blew out. I was on a heavily traffic road [XXX] . I managed to take control of truck doing about 40 mph at the time and drove it off the road to a safer spot to look at damage. Well the passenger rear tire witch was originally on the front that had the separated radial blew a chunk out of the inner sidewall. I put on the spare and went and replaced the tire with another goodyear new tire. On march 28 as i was coming home from [XXX] late at night the driver side rear tire blew as well again had to put on spare and next day took to local mechanics in [XXX] , and checked tire and again i was told that the tire separated from radial and that was the cause of blew out, they inspected all the tires at this point since this was the second tire from the same DOT set with less then 12000 miles that had separated. Well they found a third tire that had aldo separated and had a flat spot on driver side front tire, now there are 3 tires from the same set, coincidence, i dont think so i replaced the second and third tire. One the third day April 1, 2026 the passenger side front tire blew as well, now i have 4 tires that had radial separation with less then 12000 miles and less then a year old, in a mater of a month. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

On March 14 2026 i was driving from [XXX] . To [XXX] to have my tires checked because i felt a strong vibration on my steering column and truck itself, it was getting worse so i took it to my mechanic who does my regular maintenance on truck. After inspecting Tire Goodyear Wrangler SR-A ( 275 55 R20) front passenger , mechanic informed me that the tire had separated from radial. And i need to get another tire right away, since there was non in stock we did the next best thing we took the front passenger tire the affected tire put it in the back and put the rear good tire up front. The next day i was on my way to purchase the replacement tire when the tire blew out. I was on a heavily traffic road [XXX] . I managed to take control of truck doing about 40 mph at the time and drove it off the road to a safer spot to look at damage. Well the passenger rear tire witch was originally on the front that had the separated radial blew a chunk out of the inner sidewall. I put on the spare and went and replaced the tire with another goodyear new tire. On march 28 as i was coming home from [XXX] Ca late at night the driver side rear tire blew as well again had to put on spare and next day took to local mechanics in [XXX] , and checked tire and again i was told that the tire separated from radial and that was the cause of blew out, they inspected all the tires at this point since this was the second tire from the same DOT set with less then 12000 miles that had separated. Well they found a third tire that had aldo separated and had a flat spot on driver side front tire, now there are 3 tires from the same set, coincidence, i dont think so i replaced the second and third tire. One the third day April 1, 2026 the passenger side front tire blew as well, now i have 4 tires that had radial separation with 2 that had blew out chunks from inner wall, with less then 12000 miles and less then a year old, in a mater of a month. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

I am getting warning signs on the dashboard saying that my brake booster performance has failed and I need to service the brake booster , the brakes are very hard to press, I need longer stopping distances,and traction control and stability control towing harness my speed has been limited to 43 mph and it's saying that the mass air flow system is has low circuit

Engine ceased while driving and shutdown. Towed to dealership. Dealership ran diagnostic test and code P0016 came up. Its 6.2 engine has recall on other years with similar issues

The contact owns a 2019 GMC Sierra 1500. The contact stated that while driving approximately 65-70 MPH, the engine seized and made an abnormal sound, nearly causing a semi-truck to jackknife and crash into the vehicle. There was no warning light illuminated. The contact was left stranded in the west desert of Utah, where a wildfire had started, and the contact did not have phone service. Additionally, the vehicle stopped on a two-lane road with heavy semi-truck traffic, leaving the contact frightened and terrified for her safety. The contact jumped out of the vehicle. Migrants who were tending the sheep nearby assisted the contact in pushing the vehicle to the side of the road. The vehicle was towed to the dealer, where it was diagnosed with engine failure, and the dealer determined that the engine needed to be replaced. The vehicle was not repaired. The contact related the failure to NHTSA Action Number: EA25007 (ENGINE, ENGINE AND ENGINE COOLING). The manufacturer was notified of the failure, and the contact was misinformed that the model year was not included in the NHTSA investigation. The contact informed the manufacturer that she no longer felt safe driving the vehicle, regardless of the engine replacement, and the contact advised the manufacturer to guarantee that the failure would not recur after the engine replacement. The manufacturer then referred the contact to the NHTSA Hotline for assistance in investigating the safety issue. The vehicle was not repaired. The failure mileage was 122,187.

The contact owns a 2019 GMC Sierra 1500 Denali. The contact stated that while driving at an undisclosed speed on a local roadway, the oil pressure warning light illuminated. The contact stated that oil was leaking from the vehicle. The vehicle was towed to the residence. The vehicle was then taken to the dealer, where it was diagnosed, and it was determined that the engine had seized. The manufacturer was not notified of the failure. The approximate failure mileage was 71,000.

While passing a vehicle the engine failed and had to replace the engine. The cams and lifters went out.

driving and truck started to misfire (due to collapsed lifter after shop diagnosis) that then made my truck do reduced steering assist and my wheel got super hard to turn that almost sent me in the ditch at 60MPH and also turned off my Electronic Stability Control and also turned on my Service Parking Brake drove straight to the shop and parked it very lucky i did not crash and the fact that multiple people this has happend too GM need to recall from the 2019 and up for these lifters after reading about it.