"How reliable is the 2021 Gmc Terrain?"

"Based on 48 NHTSA complaints, the 2021 Gmc Terrain has a median complaint mileage of 78843 miles. The most common issue is POWER TRAIN."

"What are common problems with the 2021 Gmc Terrain?"

"The most frequently reported component in NHTSA complaints for the 2021 Gmc Terrain is POWER TRAIN, accounting for a significant portion of the 48 total complaints filed."

2021 Gmc Terrain: Reliability Data

Source: NHTSA — 48 complaints

Total Complaints

78,843mi

Median Mileage

POWER TRAIN

Top Issue

Crash Reports

When Do Complaints Happen?

Distribution of NHTSA complaints by vehicle mileage at time of report.

36,000 25th Percentile

78,843 Median Mileage

80,632 75th Percentile

What Fails?

Most reported component issues from NHTSA complaints.

POWER TRAIN

ELECTRICAL SYSTEM

ENGINE

SERVICE BRAKES

UNKNOWN OR OTHER

SUSPENSION

FORWARD COLLISION AVOIDANCE: AUTOMATIC EMERGENCY BRAKING

LANE DEPARTURE: BLIND SPOT DETECTION

FUEL/PROPULSION SYSTEM

FORWARD COLLISION AVOIDANCE: WARNINGS

Severity Assessment

Crashes

Fires

Injuries

Deaths

Sample Complaint Reports

"When driving car starting from a red light/getting on freeway or after making turn from a stop light when accelerating between 45 and 60 car shakes when shifting. Problem is getting worse. Car only has 6000 miles on it. I reported it to local gmc dealer and I was told GM is aware of the problem and ..."

"i WAS GOING TO MY SONS HOME WHICH IS LOCATED ON A STEEP DOWHILL STREET WITH SEVERAL TURNS, ONE OF THER ALMOST 90 DEGREES.aS i STARTED TO DESEND THE HILL AND GAIN SPEED, I DEPRESSED THE FOOT BRAKE. iT DID NOT RESPOND AT ALL. AS I CONTINUED TO GAIN SPEED AND COMING UP ON THE SHARP CURVE, I CO..."

"My 2021 gmc terrain with 6000 miles on odometer. When driving up hill or going around corner transmission shudders so bad that it feels like front tires are coming off. I contacted the dealer and gm and was told there is a tsb for this complaint. GM and dealer acknowledged there was a problem bu..."

Source: NHTSA ODI Complaints Database. Names and identifying details omitted.

Data source: View this vehicle on NHTSA.gov | NHTSA ODI Complaints Database. Public domain.

Methodology: Complaint counts and mileage distributions are computed directly from consumer-reported NHTSA complaints. This data represents reported issues, not failure rates — vehicles without complaints are not represented. Full methodology.

Data through: 2026-03-28