2020 GMC Terrain engine problems
57 owner complaints filed with NHTSA name the engine on the 2020 GMC Terrain — 29% of all complaints for this model year.
What owners report
“Having the start stop issue on my terrain and recently over the last few months, it has been using oil everything that sounds exactly like the recall but mine is not included. My start stop is not working and I have to get him since it had only 60,000 miles on it years ago, but nothing was done.”
filed Sep 8, 2026
“While driving, I suddenly smelled something burning. Immediately after, a warning popped up stating 'Engine power is reducing,' the check engine light came on, and I experienced a sudden, near-total loss of power braking assist, making the brake pedal extremely hard to press. I had to use intense…”
filed Aug 19, 2026
Verbatim excerpts from complaints filed with NHTSA. Reports are not independently verified.
Engine problems in other Terrain years
| Year | Reports | Share |
|---|---|---|
| 2026 Terrain | 1 | 3% |
| 2024 Terrain | 11 | 22% |
| 2023 Terrain | 14 | 37% |
| 2022 Terrain | 10 | 17% |
| 2021 Terrain | 9 | 26% |
| 2019 Terrain | 68 | 37% |
| 2018 Terrain | 53 | 24% |
| 2017 Terrain | 77 | 58% |
| 2016 Terrain | 46 | 30% |
| 2015 Terrain | 80 | 27% |
| 2014 Terrain | 123 | 42% |
| 2013 Terrain | 197 | 54% |
Other reported problem areas on the 2020 GMC Terrain
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.