2020 GMC Terrain Reliability Score & Common Problems

Owners of the 2020 GMC Terrain frequently report issues with the electrical system, particularly involving the infotainment system and instrument panel going black while driving, which affects visibility of critical information like speed and fuel levels. Complaints often mention problems with the vehicle shutting down unexpectedly or going into limp mode, sometimes accompanied by brake and steering lock-ups, posing potential safety risks. These issues appear at varied mileages, with some owners experiencing them within a few years of purchase. Additionally, several reports highlight recurring problems with the backup camera displaying a blue screen and the radio malfunctioning, including sudden volume changes or complete shutdowns. These symptoms suggest potential reliability concerns for used car buyers considering this model.

Owners report several recurring engine issues with the 2020 GMC Terrain. A common problem is a persistent engine light with code P0299, indicating turbo underboost, especially in cold weather, leading to reduced acceleration and power loss. Multiple complaints also describe sudden engine shutdowns while driving, often attributed to fuel pump module failures, with some incidents occurring at high speeds, posing safety risks. Additionally, engine failures due to internal damage, such as broken crankshafts or camshafts, are noted, typically occurring around 30,000 to 71,000 miles. These issues can lead to unexpected loss of control, increasing the potential for accidents.

Owners of the 2020 GMC Terrain frequently report issues with vehicle speed control, including stalling during acceleration and unexpected acceleration when engaging cruise control. Symptoms described include the vehicle stalling when attempting to accelerate, especially after stopping, and cruise control settings that unpredictably increase speed beyond intended limits. Complaints often involve vehicles with mileage as low as 7 miles and up to approximately 25,000 miles. Safety implications are significant, with reports of near-misses and two injuries due to brake system failures and loss of vehicle control. These patterns suggest potential risks for used car buyers considering this model.

Owners of the 2020 GMC Terrain frequently report issues with the fuel pump control module (FPCM), leading to unexpected vehicle stalls and inability to restart. Symptoms described include stalling in traffic, unresponsive throttle, and inaccurate fuel gauge readings. These problems often occur without warning and have been noted at various mileage points, with some vehicles having around 57,000 miles. Several complaints highlight significant safety implications, such as stalling in traffic, which could lead to potential accidents. Additionally, there are reports of difficulty in refueling due to faulty gauge readings, complicating the determination of actual fuel levels.

Owners of the 2020 GMC Terrain report issues with the forward collision avoidance system, primarily involving the failure of the emergency braking system to engage, which in one instance resulted in a collision. Complaints frequently mention that these safety features, including automatic braking, do not function as expected, with one owner stating these features have never worked. Another owner describes unexpected brake activations on multiple occasions, such as on Oak Hill Street and in various parking lots, despite the vehicle having less than 4,100 miles. These reports indicate potential safety implications, including the risk of crashes and unintended braking, which prospective buyers should consider.

Owners of the 2020 GMC Terrain report issues primarily related to engine failure and loss of engine power. Complaints frequently mention the vehicle losing motive power while driving at speeds around 45-50 MPH, often accompanied by illuminated check engine lights. In some cases, the engine seizes or fails to restart, with reported failures linked to components such as the vacuum pump, throttle body, and mass air flow sensor. These issues typically arise around 50,000 miles, and while there are no reports of crashes, the sudden loss of power poses potential safety risks. Buyers considering this model may find it useful to be aware of these recurring engine and cooling system problems.

Owners report steering-related issues with the 2020 GMC Terrain, including a steering wheel that locks and then jerks loose, particularly during right turns. This issue is accompanied by dashboard warnings such as the service brake assist light and ESC light, often linked with a suboptimal battery charge. Additionally, multiple owners describe a violent side-to-side wobble in the front end, occurring between 30 to 70 mph, especially after hitting a bump or during hard turns, which is noted to be more dangerous on slippery surfaces. This wobble has been observed from around 2,400 miles and persists over time, with dealerships acknowledging the problem but lacking a current fix. These issues suggest potential safety risks, including loss of control, particularly for AWD models.