2021 GMC Sierra 1500 engine and engine cooling problems
46 owner complaints filed with NHTSA name the engine and engine cooling on the 2021 GMC Sierra 1500 — 9% of all complaints for this model year.
What owners report
“The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving approximately 70 MPH, the vehicle suddenly lost motive power, decelerated, and failed to properly accelerate while depressing the accelerator pedal. The check engine warning light was illuminated. After exiting the…”
filed Jul 29, 2026
“The contact owns a 2021 GMC Sierra 1500. The contact stated that while driving 35 MPH, the engine was making an abnormal sound, and the vehicle failed to accelerate. The engine was popping and making cranking sounds, with several unknown warning lights illuminated. The vehicle was driven back to…”
filed Jul 20, 2026
Verbatim excerpts from complaints filed with NHTSA. Reports are not independently verified.
Related recalls
- Connecting rod and/or crankshaft engine components may have manufacturing defects that…Campaign 25V274000 · Apr 24, 2025
Engine and Engine Cooling problems in other Sierra 1500 years
| Year | Reports | Share |
|---|---|---|
| 2025 Sierra 1500 | 3 | 3% |
| 2024 Sierra 1500 | 30 | 9% |
| 2023 Sierra 1500 | 21 | 5% |
| 2022 Sierra 1500 | 26 | 5% |
| 2020 Sierra 1500 | 18 | 4% |
| 2019 Sierra 1500 | 23 | 4% |
| 2018 Sierra 1500 | 6 | 2% |
| 2017 Sierra 1500 | 2 | 1% |
| 2016 Sierra 1500 | 3 | 1% |
| 2015 Sierra 1500 | 1 | 0% |
| 2014 Sierra 1500 | 5 | 1% |
| 2012 Sierra 1500 | 1 | 1% |
Other reported problem areas on the 2021 GMC Sierra 1500
Counts are unique NHTSA complaints naming this component group. Complaints are unverified owner reports; mileage is computed only from complaints that included a usable odometer reading.