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
    - Chipley, FL

    I have a 2021 GC Sierra 1500, The guidance lines in the display when in reverse go from non-existent to barely visible and are not usable especially in sunlight. The service man at Miller Chevrolet in Marianna Fla says GMC is aware of the problem, that it was caused by the last update download and will be fixed by another download to correct the problem. He also says the same issue is nationwide and all trucks have the issue which I find hard to believe. 1.If that were true it would be a simple matter of a few lines of code to correct the problem. 2. I have been chasing this problem since October and have now made four trips to the dealership. 3. I cannot believe all trucks have this issue and also I suspect the same backup system is in all GMC vehicles regardless of type. 4. I cannot believe GMC would allow such a problem to exist since the last update download which was months ago. 5. I contacted GMC Customer Care in October after the dealership told me they had no idea what was causing the issue. I have had a case number [XXX] since that time. I was told on the first call that if necessary a Tech would be sent to fix the problem. Today I called asking for a tech to be sent only to be told I had to take it to another dealership and try them before a Tech could be sent! I have two questions, can you help with this and does this qualify as a "lemon law" case? Any assistance would be greatly appreciated. INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).

    Source: NHTSA WEB SITE
  • 2021 GMC SIERRA 1500
    - Brattleboro, VT

    All 4 brake rotors are warped according to my local GMC dealership. They also told me all of the inside brake pads are worn twice as much as the outer pads, which in my opinion indicates a manufacturing and/or computer controller issue. Safety is an issue when the inside brake pad wears down to metal while the outers are still over 75% of new thickness. GMC dealer told me they're seeing this on countless Sierra trucks made in the past few years but there is no recall and GMC will not cover it under warranty. First symptom was slight pulsing while braking downhill. 2-3 weeks later my brake pad wear indicator read 82% front, 88% rear. The following day it gave me an error message saying "service brake monitor" so I took it to my GMC dealer which is when they told me my brake pads and rotors all need to be replaced but the truck only had 22800 miles on it at that time. They said it could still be driven and pass inspection. Since then I have contacted GMC about them covering it and I have not made any progress. GMC has had numerous brake issues resulting in recalls in the past 3-6 years but unfortunately this particular issue has not yet reached recall status. I hope this gets resolved before I am forced to pay for brake replacements out of pocket, which nobody should have to do on a vehicle with so little miles on it. The work order invoice I uploaded indicates ""pads at wear limit, both front and rear" but it does not specify what the technician and service advisor told me regarding only the inside pads are worn. However I do have a recording of the service advisor telling me that if needed. You'll also notice that I uploaded a copy of the state inspection done by them that same day which indicates my brake system passed the requirements. Please help.

    Source: NHTSA WEB SITE
  • 2021 GMC SIERRA 1500
    - Tucson, AZ

    Within 100 miles after purchasing this truck from GMC (used with 74K miles)I got messages both on my phone and later through inspection at GMC service center that the DEF system had a problem. The check engine light came on then off as well.I was getting messages saying I only had so many miles before the DEF system needed more fluid even though the tank was full or near full. The dealer here in Tucson indicated there was a bulletin on this problem and ordered parts for the repair. I was informed it was not a recall and I would have to pay over $800.00 for this repair. To date the dealer has had my truck for 2 weeks. Additionally, another message said insufficient coolant flow so they are installing a new coolant pump to be paid for by an after market warranty which I purchased at the time I bought the truck. This repair is over $1000.00

    Source: NHTSA WEB SITE
  • 2021 GMC SIERRA 1500
    - Bensalem, PA

    The contact owns a 2021 GMC Sierra 1500. The contact stated that the grandson was driving in stop-and-go traffic, the braking system suddenly malfunctioned causing the vehicle to crash into the rear of a second vehicle. The grandson was driving approximately 10 MPH when suddenly while pressing the brake pedal to stop the message "brake failure" displayed before the vehicle crashed into the rear of the second vehicle. During the crash, no injuries were reported and a police report was taken at the scene. The vehicle was taken to the local dealer who replaced the master cylinder and brake booster and the failure was remedied. The failure mileage was 21,539

    Source: HOTLINE VEHICLE OWNERS QUESTIONNAIRE
  • 2021 GMC SIERRA 1500
    - Honolulu, HI

    The contact owns a 2021 GMC Sierra 1500. The contact stated that while operating the vehicle, the dashboard gauges, instrument cluster, and infotainment center malfunctioned and became inoperable. Additionally, while starting the vehicle, there was a loud cranking sound coming from the engine compartment and the vehicle would not immediately start. The vehicle was taken to the local dealer, but the cause of the failure was not yet determined. The manufacturer was notified of the failure, but no assistance was offered. The failure mileage was 100.

    Source: HOTLINE VEHICLE OWNERS QUESTIONNAIRE
  • 2021 GMC SIERRA 1500
    - Cartersville, GA

    The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving at an undisclosed speed, the vehicle went into Limp Mode with the check engine, DEF tank, and emission warning lights illuminated. The vehicle was taken to the dealer, and the dealer replaced several unknown sensors; however, the failure recurred. The dealer determined that the computer needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 35,000.

    Source: HOTLINE VEHICLE OWNERS QUESTIONNAIRE
  • 2021 GMC SIERRA 1500
    - Sylvester, GA

    The contact owns a 2021 GMC Sierra 1500. The contact stated that after parking the vehicle, it was discovered that the electronic multifunction tailgate had erroneously opened. Also, during the failure the tailgate struck a scooter lift that was attached to the vehicle. Both the tailgate and the scooter lift were damaged. The contact indicated that the failure had occurred on multiple occasions. The vehicle was taken to the local dealer who was unable to determine the cause of the failure and the vehicle was not repaired. The manufacturer was also notified of the failure. The contact was concerned that if a heavy load was being carried at the time of the failure it might have fallen onto a busy freeway. The failure mileage was 6,000.

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

    The driver-side mirror on my 2021 GMC sierra is unusable at freeway speed. When traveling at freeway speed the glass moves due to wind and causes the reflection in the mirror to be blurry. The reflection from the mirror is blurry to the point that I'm unable to identify objects in the mirror and it is difficult to gauge size and closing speed of any objects in the mirror. The issue has been with the vehicle since I purchased it new in June of 2021. The issue has been reproduced by two different dealership service centers and the entire driver-side mirror assembly has be replaced twice with the issue persisting. I have videos showing the issue but they are too large of files to upload on this form.

    Source: NHTSA WEB SITE
  • 2021 GMC SIERRA 1500
    - Bakersfield, CA

    I start my car and I went to pull off and the steering wheel locked up and I couldn’t turn it and it was just stuck going to sit power steering EC something. And then came home parked the car few days later try driving it and then the ABS brake light came on warning me not to go over 65 mph and my brakes pad feel really loose now.

    Source: NHTSA WEB SITE
  • 2021 GMC SIERRA 1500
    - Janesville, WI

    The contact owns a 2021 GMC Sierra 1500. The contact stated that he had received an unknown Manufacturer recall notification related to the Back Over Prevention camera. The vehicle was taken to the dealer and the recall repair was performed. Upon return of the vehicle, the grid pattern on the camera was very dim and was not visible to the contact while in use. The vehicle was taken back to the dealer where he was informed that the recall was performed correctly and that no further repair could be performed. The manufacturer was notified of the failure and a case was filed. The contact was then referred to Bob Clapper Automotive (3601 E Milwaukee St, Janesville, WI 535460) for further assistance. The vehicle was taken to the dealer; however, the dealer offered no further assistance. The dealer provided the same information as the original dealer. The vehicle was not repaired. The failure mileage was 7,000.

    Source: HOTLINE VEHICLE OWNERS QUESTIONNAIRE