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
    - NEWNAN, GA

    The engine is knocking and running rough. I took it to Christian Brothers Automotive in Newnan Ga and the advised engine replacement.

    Source: NHTSA WEB SITE
  • 2021 GMC SIERRA 1500
    - Richmond Hill, GA

    I purchased a 2021 GMC Sierra 1500 Denali (VIN: [XXX] ) from J.C. Lewis Ford in Pooler, Georgia. The dealership did not disclose an active federal safety recall (NHTSA Campaign Number: 24V-xxx / GM XXX) related to engine connecting rod and crankshaft defects that can result in sudden engine failure and loss of propulsion. The Blue Certified delivery document they had me sign includes a section requiring disclosure of any open recalls, but they left the recall section blank and checked that all recalls were explained to me. No disclosure of any recall occurred during the sale. The vehicle developed engine problems within days and is currently in GMC service. The nondisclosure put me at risk of driving a vehicle with a known safety defect. I am reporting this as a dealer nondisclosure of a federal safety recall. 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
    - Alma, KS

    The contact's grandson owns a 2021 GMC Sierra 1500. The contact stated that after the vehicle was purchased from a private seller and driven 258 miles, while his grandson was merging off the exit ramp, the engine seized. The low oil pressure warning light was illuminated. The contact stated that the check engine warning light was illuminated prior to the failure. The vehicle was towed to the contact's residence. The contact scanned the vehicle and retrieved DTCs: P0011, P0016, P006DD, and P0521, stored DTCs: P06DD P0011, and permanent DTCs: P0011 and P0016. The engine was replaced by the contact. The local dealer was contacted for parts. No further information was available. The manufacturer was not contacted. The failure mileage was approximately 100,148.

    Source: HOTLINE VEHICLE OWNERS QUESTIONNAIRE
  • 2021 GMC SIERRA 1500
    - Paulina, LA

    I just surpassed my extended warranty (5 year/100,000 miles) by a couple of thousand miles and my coolant control valve has gone out. The problem is so common that the part is on back order for months at a time. GM says that they issued special coverage for 2020-2022 models, but my dealer is telling me that my VIN is not covered. They want to charge me $2,400 to replace it. This is insane. It’s a very common problem that they know about and it’s going to almost break me. We need help!

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

    ENGINE BURNING OIL AND BLOWING WHITE SMOKE OUT TAIL PIPES. HAVE TO ADD OIL EVERY 1500 MILES OR SOONER IF TOWING. HAS BEEN AN ISSUE SINCE FIRST OIL CHANGE. VEHICLE IS NOW AT 88057 MILES

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

    While traveling to work at 75mph, a sudden an unexpected malfunction of internal engine components caused a loss of propulsion.

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

    The contact owns a 2021 GMC Sierra 1500. The contact received the recall letter for NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling). The contact called the local dealer, who confirmed there was no information from the manufacturer to move forward. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The contact had not experienced a failure.

    Source: HOTLINE VEHICLE OWNERS QUESTIONNAIRE
  • 2021 GMC SIERRA 1500
    - Pembroke Pines, FL

    I am an active U.S. Air Force member. My 2021 GMC Sierra 1500 failed GM Recall N252494003 on Sept 29, 2025 (L87 engine loss of propulsion). GM states this defect can cause sudden engine failure and loss of propulsion, increasing crash risk. Despite the confirmed failure, Ocean Cadillac (Miami, FL) told me to keep driving the unsafe vehicle and refused all Courtesy Transportation. The Service Manager admitted in writing that the engine failed, the defect can cause loss of propulsion, and the replacement engine is delayed under GM National Control for up to 3 months — yet they still denied me a loaner or rental. His statements contradict the GM documents he attached: • GM Bulletin DCS7222 says Courtesy Transportation CAN be provided during L87 recall downtime and dealers MUST consider loaners/rentals. • GM FAQ N252494002 says Courtesy Transportation IS available for this recall. • GM FAQ lists recall symptoms (check engine light, hesitation, high RPM, reduced power) — NOT battery drain. • GM states: “If the engine fails, the vehicle WILL lose propulsion.” Ocean Cadillac ignored these rules and put me back on the road in a known unsafe vehicle. As an American manufacturer, GM has a responsibility to protect American drivers. Their failure to follow recall procedures placed me, my family, and other motorists at risk. I request NHTSA investigate whether GM/Ocean Cadillac are complying with recall safety requirements and whether customers are being told to drive unsafe vehicles after confirmed failures.

    Source: NHTSA WEB SITE
  • 2021 GMC SIERRA 1500
    - Kalispell, MT

    I was traveling home from work and lost all power to the vehicle while driving. No warning lights, check engine lights came on. I was able to cross traffic and park it in a business place. I had it towed to a chevy dealership for diagnostic. They said that the timing chain came off and i would need a new engine. I had it towed to a auto mechanic shop for a second opinion and they gave the same result. The vehicle is only 4 years old with 92,000 miles on it. When i lost all power to the vehicle, I did not hear any strange noises.

    Source: NHTSA WEB SITE
  • 2021 GMC SIERRA 1500
    - St Augustine , FL

    I was driving on the freeway and my gmc Sierra at4 received a notification that I could could no longer accelerate. I pulled off to the side as safely as I could in a slanted hill in a major freeway with no shoulder. I sat on the side of the road for 45 min and then ran out of diesel gas waiting for the tow truck. We took into gmc and they said nothing was wrong, we were out of gas. But I ran out of gas waiting for the tow truck. The truck never shut off and ac still going, I just couldn’t accelerate. We’ve had the truck in the shop every single month for the past year for sensor issues and replacements and have all the documentation of the last few years of similar issues. No extensions of warranty’s nothing. Well we started to smell something burning this week and now we were told today we have a faulty fuel pump that will cost us $1,000 to fix and is not covered under our warranty. The truck is still under warranty, so why is something in relation to the power train not covered? There is a current t recall on other gmc models of this year for this fuel pump issue and the safety recall is EXACTLY what happened to us on the freeway and the issue we have now. Why has this not been extended to other GMCs????? My entire family could have died on the side of the freeway!!

    Source: NHTSA WEB SITE