2020 GMC Terrain problems & reliability
195 owner complaints filed with NHTSA for the 2020 GMC Terrain, alongside 2 safety recall campaigns. Last verified Sep 21, 2026. Complaints are unverified reports submitted by owners to the federal Office of Defects Investigation.
Each complaint is counted once (by NHTSA case number), even when it names several components.
3 complaints report injuries (5 injured).
Federal crash records (FARS 2020–2023): 2020 GMC Terrain vehicles were involved in 53 fatal crashes with 18 occupant deaths. Involvement counts are not adjusted for how many are on the road and do not imply fault or a vehicle defect.
Most reported problems
| Component | Complaints | Share |
|---|---|---|
| Service Brakes → | 63 | 32% |
| Engine → | 57 | 29% |
| Unknown / Other | 34 | 17% |
| Electrical System → | 27 | 14% |
| Power Train → | 27 | 14% |
| Fuel/propulsion System → | 25 | 13% |
| Vehicle Speed Control → | 11 | 6% |
| Forward Collision Avoidance | 8 | 4% |
| Service Brakes, Hydraulic | 7 | 4% |
| Back Over Prevention | 6 | 3% |
Component groups as classified by NHTSA. A complaint can name more than one component, so shares may sum to more than 100%.
All 26 reported components →Common symptoms owners describe
Keyword analysis of complaint narratives; one complaint can describe several symptoms.
Mileage when problems occurred
Among the 38 complaints that included a usable odometer reading, the median reported incident mileage was 49,276 miles (middle 50% between 13,565 and 91,000 miles).
Complaints by incident 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.”
Engine · filed Sep 8, 2026
“Fuel pump control module and or the in tank fuel pump failed and or isn’t making proper connection for car to run correctly. Safety was put at risk as car came to abrupt halt while driving. Driver was outside of vehicle at busy intersection for vehicle diagnostics and battery jump. Battery was removed and new battery…”
Fuel/propulsion System · filed Sep 2, 2026
“The contact owns a 2020 GMC Terrain. The contact stated that while driving at an undisclosed speed, the vehicle failed to stop as intended. The brake pedal was depressed to the floor, and the vehicle slowed down and eventually stopped. The vehicle was taken to an independent mechanic, where it was diagnosed with a…”
Service Brakes, Hydraulic · filed Aug 31, 2026
Verbatim excerpts from complaints filed with NHTSA. Reports are not independently verified.
Technical service bulletins
843 manufacturer communications (TSBs, service campaigns, warranty extensions) are on file with NHTSA for the 2020 GMC Terrain. The 10 most recent:
This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
PIP4902W · Service Bulletin/Repair Instructions · issued Sep 4, 2026
PI to help diagnose A/C concern
PIT5099J · Service Bulletin/Repair Instructions · issued Jul 21, 2026
This preliminary information communicates information about how to determine if a wheel and tires size change is available.
PIT3271Q · Service Bulletin/Repair Instructions · issued Apr 1, 2026
This preliminary information discusses a condition that may arise from the drivers window switch sending an errant message causing the vehicle to enter manual fob learn mode.
PIT5992B · Service Bulletin/Repair Instructions · issued Mar 27, 2026
This Preliminary information communicates the steps on how to save a GDS2 Session Log and upload to a Technical Assistance Case in CX Connect.
PIP6104 · Service Bulletin/Repair Instructions · issued Mar 9, 2026
This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
PIP4902V · Service Bulletin/Repair Instructions · issued Mar 9, 2026
This Preliminary information communicates to the field on how to diagnosis a GPS issue with the Telematic module with no DTC'ss
PIT6425D · Service Bulletin/Repair Instructions · issued Mar 2, 2026
This Preliminary information communicates to the field on how to diagnosis a GPS issue with the Telematic module with no DTC's
PIT6425C · Service Bulletin/Repair Instructions · issued Jan 16, 2026
This PI advised dealer technicians of possible causes of diesel fuel contamination in gasoline powered vehicles and advises of warranty direction.
PIP6098 · Service Bulletin/Repair Instructions · issued Jan 14, 2026
This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.
PIP4902U · Service Bulletin/Repair Instructions · issued Jan 8, 2026
TSBs are repair guidance manufacturers send to dealers — they are not recalls and repairs are not automatically free. Full documents are available on NHTSA’s site.
Safety recalls
The 2020 GMC Terrain has 2 NHTSA recall campaigns — recall repairs are free at franchised dealers regardless of the vehicle’s age.
Check whether your specific vehicle is affected
Recall campaigns often cover only certain VIN ranges. Enter your VIN on the official NHTSA site to confirm whether your vehicle is included and whether the repair is still open.
Check VIN on NHTSA →Buying a used 2020 GMC Terrain?
- · Decode the seller’s VIN with our free VIN decoder to confirm the exact year, engine and trim.
- · Check for unrepaired recalls by VIN on NHTSA’s official lookup — recall repairs are free.
- · Among complaints with usable mileage, the median reported incident mileage was 49,276 miles. This does not predict when a particular vehicle will develop a problem.