2020 GMC Terrain service brakes problems
61 owner complaints filed with NHTSA name the service brakes on the 2020 GMC Terrain — 33% of all complaints for this model year.
What owners report
“While driving north in interstate 79, the brakes became very hard to push making it difficult to stop the vehicle. We got off the interstate and proceeded back home. The brakes were as hard as a rock to push and it was difficult to stop the vehicle. When this happened, the check engine light came…”
filed Jul 30, 2026
“Vacuum pump failure causing sudden and unexpected hard brake pedal and loss of braking coming off the highway. Ended up catastrophic engine failure. This is the SECOND incident with this vehicle of the exact same problem. GMC refuses to address this issue and continues to risk the lives of their…”
filed Jul 23, 2026
Verbatim excerpts from complaints filed with NHTSA. Reports are not independently verified.
Service Brakes problems in other Terrain years
| Year | Reports | Share |
|---|---|---|
| 2026 Terrain | 3 | 13% |
| 2024 Terrain | 2 | 4% |
| 2022 Terrain | 1 | 2% |
| 2021 Terrain | 8 | 24% |
| 2019 Terrain | 58 | 33% |
| 2018 Terrain | 66 | 31% |
| 2017 Terrain | 2 | 2% |
| 2016 Terrain | 5 | 3% |
| 2015 Terrain | 8 | 3% |
| 2014 Terrain | 9 | 3% |
| 2013 Terrain | 7 | 2% |
| 2012 Terrain | 5 | 1% |
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.