10.0

really awful
Crashes / Fires:
0 / 4
Injuries / Deaths:
0 / 0
Average Mileage:
5,756 miles

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problem #60

Jan 162025

Sierra 1500

  • miles
I got off work started my truck heard a few pops. As I was driving the vehicle started jerking like the brakes were being applied. Then I noticed a yellow engine light and a ESC light come on. I pulled over to check vehicle and all the lights went off. Dealer was just a few miles away. So I started back up and drove to dealer. On the way to dealer vehicle started a tapping noise. Then a new message flashed something about my steering will be affected. I got I to dealer safely. Where I left the truck for repairs.

- Greenwood , IN, USA

problem #59

Sep 112024

Sierra 1500

  • miles
We had to replace the transmission at 70,000 miles even though problems were reported to the dealer at 53,340. This repair costed $2300 on a 1 year old truck. Then we needed to replace a solenoid circuit which was not covered under warranty. We repaired this 2x (the second time covered). Then at 147,000 miles 9/24, there was a cylinder misfire which bent the push rod and collapsed lifter. This engine repair cost $8300 dollars. Who has to replace an engine on a truck that's 3 years old. This is a defect. Please help us. We have spent over $10,000 on repairs. We faithfully do our changes and service.

- Sanbornton, NH, USA

problem #58

Oct 142024

Sierra 1500

  • miles
Multiple injector and lifter failures. Occurred on 2 separate occasions. Taken to dealer the first time. Told injector failure and lifter failure. Less than a week later experienced multiple lifter failures. Taken to dealer again for repair. They only replaced some of the affected lifters, even though TSB from GM recommends replacement of all of them. Currently awaiting failure of additional components not replaced. There was no warning of either occurrence. Was only driving 45 mph on my way home the first time. The second occasion was on initial start up at Dr office. Opened a claim with GM on my own, as dealership was negligent or unwilling to contact GMC about these failures, even though I provided them with the appropriate TSB directly from GM.

- Lacenter, WA, USA

problem #57

May 022024

Sierra 1500

  • miles
Engine failed due to a loss of oil pressure. Rod bearing failed which cause metal to be dispersed throughout the engine causing the engine to seize from a sudden loss of oil pressure from oil pump failure. Engine was replaced in June 2024 failure happened in May 2024. While driving a system message came on DIC that stated pull over immediately to prevent engine damage and no oil pressure. I was driving uphill with cars on my right in the #2 lane. Engine shut off before I could pull over resulting in decreased braking power and a lack of steering. I almost hit 2 vehicles trying to pull over to get my family to safety on the right hand shoulder. I couldn-??t pull over to the left hand shoulder as there was a guardrail in the way. When I got my vehicle pulled over the only thing that stopped my vehicle from going over the cliff was a bunch of wood chips on the right hand shoulder. From the time the warning lights came on to the time the engine shut off and seized was maybe 5 seconds. It took 31 days to replace the engine and the dealership did an inspection on the engine. There was absolutely no warning there was any problems until the lights came on. My wife and [XXX] and [XXX] were in the vehicle at the time this happened. It was so dangerous where we broke down California Highway Patrol stayed behind my vehicle with its lights on. It was also a fire hazard with the exhaust sitting on the dry bark. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Orland, CA, USA

problem #56

Oct 112021

Sierra 1500

  • miles
I purchased this vehicle new in 2021. It is an Ultimate Denali trim level with a 6.2 engine. Within the first year, the driver's side head on the engine had a massive failure with only 7,000 miles. I started up the vehicle and was parked idling briefly when several light came on along with a rough idle and some exhaust smoke. I contacted On Star, who could not diagnose the problem. The vehicle was disabled and ended up being towed to the dealer, where it was being repaired for 10 days. The lifters, valves and push rods were replace. The mechanic admitted there was an internal GM problem with the 6.2 engine. I asked for the same repair be made on the passenger side head. The GM dealer refused, knowing of the faulty factory installed parts. The polished tailpipe tips were not replace and were stained by the black exhaust. They are still stained this day. I purchased this vehicle for my retirement to tow my RV. Now, I have been reluctant to travel because of the other head letting go on me somewhere out west, operating under a work load. I know of two other people who purchased new GM vehicles with the 6.2 engine, who experienced the same failure, with around the same mileage on their vehicles.

- Palm Bay, FL, USA

problem #55

Dec 072021

Sierra 1500

  • miles
at 8500 miles the engine had lifter go out while I was driving down the highway cause to truck to vibrate and becoming on unsteady causing me to pull over in the middle of traffic. later at 36500 miles it had another lifter go out this time I was driving home at a slower speed but still cause me to have to pull over vert fast as the vehicle became unsteady and vibrated causing all the alarm to come on. Both times the truck was fixed under warranty nut they replaced it with the same parts that are causing the problems. Soon my truck will be off warranty and this will come out of my pocket.

- Brewster, WA, USA

problem #54

Jan 182025

Sierra 1500

  • miles
L87 engine problems. I have had failed lifters, on top of transmission issues and a current oil consumption issue where I have to add two quarts of oil (sometimes more) without any indication of low oil. I took my vehicle into the local dealership and the technician asked if I had gotten any low oil indicator and I stated no. He proceeded to tell me it had little to no oil in it. Imagine this at highway speeds and sudden engine seizure.

- Spruce Pine, NC, USA

problem #53

Nov 072024

Sierra 1500

  • miles
The engine blew up at 67,000 mile while driving down the road. Not sure what happened but there was no warning signs at all. The dealership said they couldn-??t know for sure what happened but most likely the oil pump went bad. I have spoken with a few people that have had this same problem with the 6.2 liter engine. It needs to be looked into because this could have caused a major accident on the highway.

- Gardendale , AL, USA

problem #52

Oct 112024

Sierra 1500

  • miles
On memorial day weekend 2023 my truck,2021 GMC Sierra AT4 was making a awful noise. I pulled over and vehicle died. had it towed and the warranty covered new engine replacement at 54678 miles(large deposit of metal in the oil pan). June of 2024 again, traveling out of town and pickup making terrible noise and shaking at 76651 miles. Replaced lifters in vehicle. October 11, 2024 took vehicle in for oil change, drove 25 miles and vehicle making terrible noise. Pulled over and pickup died. Had it towed to dealer and they are saying it needs a new engine. ( 87000 miles) they are saying its out of warranty. There seems to be a serious problem with this engine( 6.2) in all the research I am finding. I now have a pickup that I am still making payments on, that I cannot drive.

- Conrad, MT, USA

problem #51

Sep 272024

Sierra 1500

  • 133,000 miles
The contact owns a 2021 GMC Sierra 1500. The contact stated while driving 45 MPH, there was an abnormal ticking sound coming from the vehicle. The contact stated that several unknown warning lights were illuminated. The vehicle was placed on a trailer and was taken to an independent mechanic who stated that the lifter and cam shaft needed to be replaced. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was contacted and referred the contact to the NHTSA Hotline to report the failure. The failure mileage was approximately 133,000.

- Conway, SC, USA

problem #50

Sep 232024

Sierra 1500

  • miles
Per the dealership: Lifter failure, crankshaft failure, metal shavings in the oil. Complete engine failure.

- Leesburg, VA, USA

problem #49

Sep 032024

Sierra 1500

  • 81,000 miles
The contact's husband owns a 2021 GMC Sierra 1500. The contact stated that while her husband was driving 80 MPH, the vehicle stalled. Additionally, the "Shift to Neutral and Restart" message blinked. The vehicle was steered to the side of the road where the vehicle failed to restart. The vehicle was towed to an independent mechanic where the failure was not able to be replicated. The vehicle was then towed to the dealer where it was suspected that the crankshaft bearing had seized, putting pressure on the starter, causing a short. The contact was informed that the engine needed to be taken apart for a proper diagnostic test. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 81,000.

- Carneys Point, NJ, USA

problem #48

Aug 132024

Sierra 1500

  • miles
The engine locked up on the truck due to bad lifters. It has the 6.2L engine and after talking to several mechanic shops and research online this is a very common issue. GM is having to put lots of new engine in under warranty due to this issue. They need to have a recall to fix a known issue that is costing people thousands of dollars to replace the whole engine in the truck. We was driving down the hey today and with no working at all the truck died and and would not crank back over. We had the truck towed to a repair shop to find out that our truck had the same issue that lots of people are having and now it-??s gonna cost us several thousand dollars to have fixed when realistically GM should be paying to fix this problem.

- Yukon, OK, USA

problem #47

May 062024

Sierra 1500

  • miles
On the evening of 5/6/24, my husband was driving home in our 2021 GMC Sierra 1500 when the truck started to run hard, shaking, and the check engine light came on and was blinking. He pulled onto the side of the road immediately and more messages were coming across the dashboard. The truck was towed to a dealership that same night. Once the dealership assessed what was wrong, we were advised by the dealership who confirmed the lifters failed. The truck is currently still sitting at the dealership as we're waiting for the parts because we've been told multiple times that the parts are on backorder. I understand the truck is available for inspection as its been sitting on the lot since 5/6/24. This is the first time this has happened to the truck, zero prior issues. The truck has great service records and has always been properly maintained. We are currently still under the manufacturer warranty. To date, the dealership is still in possession of the truck for 90 days, and we still do not have any ETA on when the parts will arrive/truck will be fixed.

- Dayton, ME, USA

problem #46

Jun 142024

Sierra 1500

  • miles
On [XXX] at approximately 3 pm I left my house and was traveling on [XXX] in Fort Mohave Arizona I was only traveling 7 miles. When I looked at the temperature in the cab was 121 degrees a few moments after the display system went black and never turned back on. I arrived at the store 4 minutes after the display shut off with no warning lights or any type of notification on my phone, I had rolled down the windows to get air in the cab to see if that would help cool down if needed. I was in the store 20 minutes. I returned to the truck turned it on and everything was normal, from there I drove back home nothing happened on my drive back the display was working. At 8 30pm I was traveling on [XXX] Driving towards a casino called Avi. I had the driver's side window halfway down when I smelled a faint plastic burn thinking it was coming from the outside because I had the window halfway down. That is when the cab of the GMC filled up with smoke that came in thru the air vents and flames started to show coming from the defrost vents and under the hood while I was driving. I had to stick my head out of the window to see where I could pull over without starting a huge brush fire. As I pulled over and the truck within seconds fully ignited into flames. Enough time to grab my belongings that I was able to save. My life was at risk by this vehicle igniting while I was driving. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Fort Mohave, AZ, USA

problem #45

May 242024

Sierra 1500

  • 46,000 miles
The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle failed to accelerate as needed and made an abnormal sound. The contact assumed that the sound was coming from the transmission and the vehicle was taken to a dealer. The dealer diagnosed the vehicle and suggested that the failure might be a pulley or a rod bearing failure. The contact took the vehicle to another dealer who confirmed a rod bearing failure. The manufacturer was not made aware of the failure. The vehicle was not repaired. The failure mileage was approximately 46,000.

- Schertz, TX, USA

problem #44

Oct 302023

Sierra 1500

  • miles
The coolant control valve is faulty and needs to be replaced. GMC and the dealership know about the issue (Bulletin No. PIP5791), but are not fixing it in a timely manner. This is a safety concern as the system will automatically reduce engine power, which is a major concern when towing and/or in mountainous terrain.

- Arvada, CO, USA

problem #43

May 042024

Sierra 1500

  • miles
The component that has failed is the engine coolant flow control valve AC Delco part number 55516369. Unfortunately the part is still installed on the vehicle. It has been taken to a dealer and this is a known issue but no recall has been issued. The check engine comes on sometimes but not always, sometimes the pickup has plenty of power to drive and sometime it will barely pull itself, all in the same trip without shutting the ignition off. The symptoms first started in December of 2023, but were sporadic, now it is nearly everytime the pickup is started. It is extremely dangerous to drive this vehicle when it has a problem. You cannot tell if it will accelerate normally or is you will push the pedal and it does nothing. The part to repair the problem is on backorder and no release date is yet available. We have been waiting for 3 months and still no word on when this will be repaired.

- Cimarron, KS, USA

problem #42

Jan 152023

Sierra 1500

  • miles
I purchased this vehicle used with approx 16k miles on it. Not long after getting it - as I was driving it started dinging and then would shut off. Sometimes I-??m in the fast lane going 75Mph and it-??ll just shut off. The dealership can-??t get it to repeat itself. They said they-??ve heard of it happening before but it throws different codes. There-??s no rhyme or reason to causing it to shut off, but here lately I don-??t even get the warning bell. It just dies on me. As soon as i shift it to neutral and press start it-??ll restart instantly. But it-??s scary nonetheless, and causes me to drop speed instantly and poses a safety risk especially when I have semi-??s or other vehicles close behind.

- Meridian, OK, USA

problem #41

Oct 292023

Sierra 1500

  • miles
"Service parking brake" "steering assist is reduced drive with care" comments showed up on screen-??check engine light on, truck shaking/ vibrating completely as if wanting to turn off this all happened while driving on the road and randomly happened-??please help..very Concerned

- Edinburg, TX, USA

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