2018 GMC Terrain problems and complaints
Owners have filed 224 complaints with NHTSA about the 2018 GMC Terrain. The most-reported areas: Service Brakes (84), Engine (55), Power Train (41).
Key takeaways
- 224 owner complaints on file with NHTSA.
- 14 involve a crash, 1 a fire, 12 reported injuries.
- Complaints are unverified owner reports; recalls are confirmed defects.
| Component | Complaints | Share |
|---|---|---|
| Service Brakes | 84 | 38% |
| Engine | 55 | 25% |
| Power Train | 41 | 18% |
| Unknown Or Other | 35 | 16% |
| Electrical System | 35 | 16% |
| Air Bags | 14 | 6% |
| Hydraulic | 13 | 6% |
| Fuel/Propulsion System | 12 | 5% |
| Forward Collision Avoidance | 8 | 4% |
| Vehicle Speed Control | 8 | 4% |
| Steering | 7 | 3% |
| Electronic Stability Control (esc) | 7 | 3% |
One complaint can name several components, so shares add up to more than 100%.
| Version | Overall | Front | Side | Rollover |
|---|---|---|---|---|
| 2018 GMC Terrain SUV FWD Later Release | 5/5 | 5/5 | 5/5 | 4/5 |
| 2018 GMC Terrain SUV AWD Later Release | 5/5 | 5/5 | 5/5 | 4/5 |
| 2018 GMC Terrain SUV AWD Early Release | 4/5 | 5/5 | 4/5 | 4/5 |
| 2018 GMC Terrain SUV FWD Early Release | 4/5 | 5/5 | 4/5 | 4/5 |
Latest complaints, as filed
Owner-written and unverified by NHTSA.
Service Brakes,engine - filed 2026-10-14
On XXX while driving my 2018 GMC Terrain SLE 1.5L turbo on the highway at approximately 70 MPH near [XXX]. I experienced a sudden loss of power brake assist without any prior dashboard warning lights or messages. I was traveling with children to [XXX] for a youth wrestling tournament, approximately 5 hours from my resi...
Unknown Or Other,service Brakes,engine - filed 2026-09-30
Without any type of warning, I was driving down the road when my car started making a knocking/ticking type noise then my engine light came on. I attempted to hit my brakes and stop, and I had no control. There was no brakes without pushing it all the way to the floor it was very hard to get my car to stop. I managed t...
Steering,suspension - filed 2026-09-25
Dear [Manufacturer], I am writing to report a serious safety concern with my [year, make, model]. A bolt from the idler arm/undercarriage came off after becoming severely rusted. I had the vehicle inspected by a repair shop, but they could not determine why the bolt failed or why it had rusted to this extent. This is...
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More for the 2018 GMC Terrain
Complaints are reports filed by owners with the National Highway Traffic Safety Administration. NHTSA publishes them without verifying them, and counts rise with how many cars were sold, so compare years of the same model rather than different models. Crash ratings are NHTSA's own 5-Star Safety Ratings results.