Common problems
GMC Terrain Common Problems
We grouped the top NHTSA owner-complaint categories across 9 GMC Terrain model years, then counted how often each issue recurs. The result shows patterns worth inspecting without pretending every vehicle will have them.
Data updated April 2026
- Owner complaints
- 675
- Top recurring issue
- Electrical System
- Crash reports
- 34
- Fire reports
- 6
9 model years
8 affected years
Owner-reported severity signal
32 injuries · 0 deaths
Pattern overview
Most reported GMC Terrain problem categories
Electrical System
92complaints representedAppears among the leading issues for 8 model years; highest in 2018.
Power Train
135complaints representedAppears among the leading issues for 7 model years; highest in 2019.
Unknown Or Other
69complaints representedAppears among the leading issues for 7 model years; highest in 2018.
Engine
55complaints representedAppears among the leading issues for 6 model years; highest in 2019.
Service Brakes
124complaints representedAppears among the leading issues for 4 model years; highest in 2018.
Fuel Propulsion System
19complaints representedAppears among the leading issues for 3 model years; highest in 2022.
Air Bags
12complaints representedAppears among the leading issues for 2 model years; highest in 2018.
Fuel System, Gasoline
12complaints representedAppears among the leading issues for 2 model years; highest in 2022.
Vehicle Speed Control
8complaints representedAppears among the leading issues for 1 model year; highest in 2020.
Back Over Prevention
7complaints representedAppears among the leading issues for 1 model year; highest in 2019.
What owners reported
Issue summaries by GMC Terrain model year
SERVICE BRAKES
Owners of the 2018 GMC Terrain frequently report issues with the brake vacuum pump, leading to a hard brake pedal and loss of braking ability. Symptoms described include the brakes becoming difficult to depress, the "Brake Assist" warning activating, and in some cases, the engine suffering damage due to metal fragments from the vacuum pump. These issues commonly occur around 90,000 to 132,000 miles. Safety implications are significant, with one reported crash and injury, and multiple accounts of near misses due to sudden loss of braking power. Potential buyers should be aware of these recurring brake system failures and the associated repair challenges.
Severity signals: 1 crash, 0 fire, 1 injury reports
POWER TRAIN
Owners of the 2019 GMC Terrain frequently report issues with the power train, specifically highlighting problems with the transmission and vacuum pump. Common symptoms include the vehicle slipping out of gear, jerking during acceleration, and unexpected shifts into neutral. Many complaints mention vacuum pump failures leading to brake issues, often resulting in hard brakes or loss of braking capability. These problems typically occur around 45,000 to 100,000 miles. Safety concerns are evident, as some owners describe near-miss accidents due to sudden loss of engine power or braking ability, particularly at highway speeds. Prospective buyers should be aware of these recurring issues and the potential for costly repairs.
SERVICE BRAKES
Owners of the 2020 GMC Terrain frequently report issues with the brake vacuum pump, which can fail and lead to a hard brake pedal, making the vehicle difficult to stop. Symptoms often include a "service brake assist" warning on the dash and, in some cases, a check engine light. The failure is sometimes accompanied by the vacuum pump breaking apart and causing damage to the camshaft and engine. Complaints often occur between 37,000 to 156,000 miles. Some reports include crashes and near-misses due to sudden brake loss, highlighting significant safety concerns. Buyers considering this model should be aware of these commonly reported issues and the potential for costly repairs.
Severity signals: 4 crash, 0 fire, 0 injury reports
SERVICE BRAKES
Owners of the 2019 GMC Terrain commonly report issues with the brake vacuum pump leading to brake failure. Typical symptoms include a hard brake pedal, inability to stop the vehicle, and lack of warning lights prior to failure. These issues often occur around 60,000 to 86,000 miles, with some reports indicating engine damage due to debris from the failed pump. Safety implications are significant, with one crash reported resulting in three injuries, and numerous accounts of near-misses due to brake failure. Potential buyers should be aware of these patterns and consider the implications for vehicle safety and associated repair costs.
Severity signals: 1 crash, 0 fire, 3 injury reports
POWER TRAIN
Owners of the 2018 GMC Terrain frequently report issues related to the transmission and powertrain, particularly involving erratic gear shifting and transmission failures. Symptoms described include the vehicle unexpectedly decelerating, failing to accelerate, and in some cases, the transmission slipping into neutral or park without warning. These issues often occur around 50,000 to 130,000 miles. Safety implications are evident, with reports of vehicles losing propulsion in traffic and narrowly avoiding collisions. Additionally, some owners mention engine power reduction warnings and vacuum pump failures, which can lead to significant engine damage and costly repairs. These patterns suggest potential reliability concerns for prospective buyers, especially those considering high-mileage vehicles.
Severity signals: 1 crash, 0 fire, 0 injury reports
ELECTRICAL SYSTEM
Owners of the 2018 GMC Terrain frequently report issues with the vehicle's electrical system, particularly concerning the infotainment system and door locks. Complaints often describe the infotainment system malfunctioning, with screens going blank or switching stations unexpectedly, and some owners note problems with the system at around 77,000 miles. Additionally, multiple owners experience door lock failures, including instances where they are unable to enter the vehicle. Safety implications are significant, with reports of the vehicle shutting down unexpectedly, sometimes in traffic, and one report involving a crash. These issues, along with reports of electrical harness corrosion and engine control module failures, suggest potential reliability concerns for used car buyers considering this model.
Severity signals: 1 crash, 1 fire, 0 injury reports
POWER TRAIN
Owners of the 2020 GMC Terrain frequently report issues related to the power train, particularly involving transmission failures and acceleration problems. Symptoms commonly described include the vehicle failing to accelerate from a stop, hesitating before moving forward, and unintended shifting into neutral. These issues often occur around 60,000 to 100,000 miles. Several reports highlight safety concerns, such as the vehicle stalling or losing power suddenly, posing risks in traffic or during turns. Additionally, some owners mention problems with the turbocharger and excessive oil consumption leading to engine damage. Potential buyers should be aware of these patterns, especially if considering a high-mileage vehicle.
ELECTRICAL SYSTEM
Owners of the 2019 GMC Terrain frequently report issues with the vehicle's electrical system, particularly involving the backup camera, infotainment system, and engine power. Complaints often describe backup cameras displaying a blue screen or service message, infotainment systems with erratic volume control, and intermittent loss of engine power accompanied by warning lights. These problems are reported across various mileage ranges, with some occurring shortly after purchase and others after significant use. Safety concerns are noted, including instances of the vehicle stalling while driving, which could lead to dangerous situations, and one report of a fire linked to the air conditioning system causing injuries. Buyers should be aware of these patterns when considering a used 2019 GMC Terrain.
Severity signals: 0 crash, 1 fire, 2 injury reports
Pre-purchase inspection
What to check on a used GMC Terrain
When problems are reported to begin
- Transmission fluid leaks — 3,500–6,300 miles on the 2025 model-year record
- Transmission failures — 2,400–22,000 miles on the 2024 model-year record
- Fuel system failures — 25,000–42,000 miles on the 2024 model-year record
- Fuel pump failures — 12,000–42,000 miles on the 2023 model-year record
- Electrical system failures — 12,000–48,000 miles on the 2023 model-year record
- Fuel pump module failure — 19,000–53,000 miles on the 2022 model-year record
- Engine failures — 21,000–60,300 miles on the 2022 model-year record
- Steering lock issues — 6,000–18,000 miles on the 2022 model-year record
Buyer red flags
- Check for transmission fluid leaks and verify fluid levels
- Test shifting into park and drive to ensure proper engagement
- Inspect brake system for stiffness and verify brake control module functionality
- Test key fob functionality for unlocking and starting the vehicle
- Verify infotainment system operation and check for update errors
- Inspect windshield for any visual distortions or defects
- Test steering stability at highway speeds for swaying or control issues
- Inspect transmission for erratic shifting or slipping
How to interpret the counts
Complaint totals are not failure rates
A popular or older model can accumulate more complaints simply because more vehicles exist and have spent longer on the road. The categories above aggregate the counts embedded in each model year's leading issues. Use recurrence across years and severity signals to decide what to inspect; use the VIN and a mechanical inspection to judge one car.
Source trail
Where this GMC Terrain data comes from
VinExposed combines model-level research with the vehicle-specific history you get from a VIN. Reliability scores and complaint patterns come from Auto Reliability Index's GMC Terrain research, which analyzes NHTSA records and independent repair data.
Recall counts describe a model year, not the repair status of one car. Confirm the exact VIN with the official NHTSA recall lookup and a vehicle-history report before buying.
Buyer questions
GMC Terrain research FAQ
What is the most common GMC Terrain problem?
Electrical System is the broadest recurring complaint category in the available model-year records, appearing among the top issues for 8 years with 92 complaints represented.
Which GMC Terrain year has the most reported problems?
The 2018 has the largest electrical system count among the years where that category appears. Compare the full year record because a different year may lead on another problem category.
Do NHTSA complaints prove a GMC Terrain has a defect?
No. Owner complaints are unverified reports and can be duplicated or influenced by sales volume and vehicle age. They are useful patterns to investigate alongside recalls, service records, inspection results and the exact VIN.
Check the actual car
Model research narrows the list. The VIN confirms the car.
Check title brands, accidents, odometer history, auction records and recall status for the specific GMC Terrain you are considering.