2021 GMC SIERRA 1500 Complaints

View complaints related to 2021 GMC SIERRA 1500. The complaints found here are submitted by actual consumers with first hand experience. There are more than 530 complaints submitted for the 2021 GMC SIERRA 1500. You can submit your own complaint to the NHTSA or call the Hotline, Monday-Friday 8am to 8pm at (888) 327-4236, TTY: (800) 424-9153.

  • 2021 GMC SIERRA 1500
    - Montgomery, AL

    The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 65 - 70 MPH, there was a knocking sound coming from the vehicle and the vehicle shut off. There were unknown warning lights illuminated. The vehicle was towed to an unknown location. The local dealer was contacted. The vehicle was not diagnosed or repaired. The vehicle was taken to an independent mechanic who determined that there was a solid engine bottom and bearing failure. The contact was informed that the engine needed to be replaced. The vehicle was repaired. but the failure recurred, and the vehicle failed to start. The manufacturer was contacted and informed of the failure. The failure mileage was approximately 83,000.

    Source: HOTLINE VEHICLE OWNERS QUESTIONNAIRE
  • 2021 GMC SIERRA 1500
    - Bakersfield, CA

    I wanted to reach out to see if there is anything in addition to the lemon law. I bought a 2021 GMC Sierra with 38,000 miles on it around March of last year. There was a motor defect which was covered by the warranty. I was driving and it stopped in the middle of the road so I had to safely maneuver out of the main road. The truck was towed to my house with 45,184 miles on it, until the GMC dealership could take it in to inspect. They did take a while to get me a rental because everything was backed up. They said they could rent me out a truck due to not being their brand and that it only covers a certain amount. It got taken in by the dealership on 7/15/2024 and ended up getting the truck back repaired on 8/27. I did get the truck back and have been having it, I am just worried about it breaking down or anything of that nature. I just wanted to know if there is any further process I should do or since they repaired it there should be no issue.

    Source: NHTSA WEB SITE
  • 2021 GMC SIERRA 1500
    - Mandeville, LA

    First engine blown 31,904 miles, Lifter failure. Replaced with re-manufactured engine. Second engine failure at 68,000 miles, Piston rod failure. Piston blew thru engine block and engine bay caught on fire.

    Source: NHTSA WEB SITE
  • 2021 GMC SIERRA 1500
    - Duluth, MN

    I had purchased a 2021 GMC Sierra equipped with the 6.2 liter motor in October of 2021. Within two weeks, my engine was experiencing problems. There was no service lights on the dash, and my truck suddenly shut off while on a busy road. I was able to coast to the side of the road, however it was a driving lane with no shoulder which made the situation dangerous. I was able to restart the engine after some time, and eventually get the vehicle off of the roadway, thankfully I got out of the driving lane without being struck by another vehicle. The truck had approximatley 1000 miles at this time and was brand new. I ended up needing a complete engine replacement due to failed crank bearings and connecting rods. I was told it was a crankshaft issue. After the complete motor replacement, sometime during the next year I was experiencing oil burning issues. On this second motor, a GM dealer had to completley rebuild the top end of the motor and install new piston rings. This is now a total of two motor failues in under 30,000 miles.

    Source: NHTSA WEB SITE
  • 2021 GMC SIERRA 1500
    - Gillett, TX

    Tried to accelerate and heard a loud pop and the truck didn’t accelerate. Pretty much went idle in the middle of the road. The check engine light, the traction control light, and the ABS light all came on. I would press on the gas and it would rev but nothing would happen till a few seconds later the RPM’s would shoot up and you could tell it was trying to get going but didn’t very slowly and I would hear a clicking noise every time it was around the second gear. It put my children and myself in danger because traffic was heavy with vehicles going 70+mph merging into one lane. Took it to a dealership and they stated it was the the push rod and camshaft were damaged and all 16 lifters should be replaced and camshaft also. No, the vehicle has not been inspected by any of those except a car dealership and a mechanic. This problem first appeared the day it happened and continued after. Even took it to a mechanic and had all 16 lifters changed and problem still persists. Spent over $6,000 on a brand new truck and it is still undrivable because every time you get in to drive it the cylinder #2 misfires.

    Source: NHTSA WEB SITE
  • 2021 GMC SIERRA 1500
    - Smithfield , VA

    See attached vehicle repair orders/Carfax/vehicle registration. The trucks transmission has been slipping/jerking hard since I pulled off the lot at dealer ship. Its burning oil no leaks has been doing so since the day I drove off the lot at dealership. I have asked to fix or address and problem still exist. They sold vehicle as everything was working The Left head light wasn’t working the day I drove off the lot didn’t notice until I got home I reached back out to dealer to explain and said light had a short in kept truck for almost a week said the were going to replace the head light and never did. The remote start wasn’t working the same day i purchased the truck but sold it as everything is working. I went to try it as I was getting ready to leave dealership and did nothing. Then I discovered the fog lights were missing, and dealer said oh there was never any in the truck but if you read the service paper work there was lights in truck. Took truck back to address the issues the next day or so after purchase I was told to bring truck back the following week. All the conditions still exist and I should not be having any of these issues as the sold vehicle nothing wrong. They even had an October inspection saying everything was SAT but I get in truck no fog lights and left head lamp is not working but they performed an 360 inspection….yeah no way… This truck is doing the same as my 2021 chevy Silverado but there is nothing wrong with vehicle according to dealership. Sold A Lemon if you asked me… ***Highlighted in yellow is a recall that the dealership has not done nor can they find anything on the recall**** *****Power train**** Recall date 2024-10-24 Recall no. 24V797000 General Motors, LLC (GM) is recalling certain 2020-2022 Chevrolet Silverado 1500, 2500, 3500, GMC Sierra 1500, 2500, 3500, 2021 Cadillac Escalade, Escalade ESV, Chevrolet Tahoe, Suburban, GMC Yukon, and Yukon XL vehicles equipped with diesel en

    Source: NHTSA WEB SITE
  • 2021 GMC SIERRA 1500
    - St Amant, LA

    Motor seized up while going around 65mph. Truck lost all power and would not start brought to dealer and they said that it was the crankshaft bearings and something with the connecting rods, the deal told me that they don’t know what to do and is waiting on GM. There is a recall for these issues but no fix. I’m just waiting for the dealer to tell me what’s next but they don’t even know.

    Source: NHTSA WEB SITE
  • 2021 GMC SIERRA 1500
    - Saint Amant, LA

    The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving approximately 55 MPH, the vehicle suddenly experienced a loss of automotive power. During the failure, the message "Shift into Neutral to Restart" was displayed. The vehicle was later towed to the local dealer, who diagnosed that the piston bearings had seized, causing damage to the engine. The engine was replaced along with the radiator, oil cooler and oil cooler hoses, intake manifold, mega fuse, and starter. The manufacturer was notified of the failure. The contact was informed that the VIN was recently included in the NHTSA Campaign Number: 25V274000 (ENGINE AND ENGINE COOLING). The contact stated that the vehicle had experienced the failure listed in the recall. The failure mileage was 122,691.

    Source: HOTLINE VEHICLE OWNERS QUESTIONNAIRE
  • 2021 GMC SIERRA 1500
    - Attleboro, MA

    The contact owns a 2021 GMC Sierra 1500. The contact stated that there was an abnormal ticking sound coming from the vehicle while idling. There was no warning light illuminated. The vehicle was taken to an independent mechanic to be diagnosed. The contact was then notified of NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The local dealer was not made aware of the issue. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The failure mileage was approximately 33,000. VIN tool confirms parts not available.

    Source: HOTLINE VEHICLE OWNERS QUESTIONNAIRE
  • 2021 GMC SIERRA 1500
    - Flanders , NJ

    Engine power reduced, could not accelerate, fuel pump issue and was bucking the engine Went to dealer and complained as gmc not working to help me, dealer fixed issue but said no other complaints out there and car was fixed, gmc called me several times and keeps saying no issues with the vin associated. The car was fixed but I am stuck with a truck that is probably not saleable once these issues continue. This issue happened initially with 30 k on it and dealer could not find the issue and this times at 61500 happened again

    Source: NHTSA WEB SITE