2019 GMC Terrain Reliability Report

Catastrophic engine failure is the worst pattern. A broken vacuum pump sends debris into the engine, and repairs include timing chains, cam phasers, or a full engine replacement. Two reports involve fire, including a highway shutdown with flames under the hood at 14K miles. New cars lose power under hard acceleration with misfire warnings, and one had a turbo tube blow off at 1000 miles. Other reports describe overheating with oil in the coolant and a transmission that drops into Park while driving.

The panoramic sunroof glass shatters while driving, with no object striking it. One case came within days of purchase. Several filings repeat the vacuum pump failure: a stiff brake pedal paired with "engine speed reduced" or lost power on the highway, sometimes followed by camshaft and timing chain repairs. Other reports cover a dead rear camera module, a rear sunshade off its tracks, and a manual liftgate that opens low enough for tall drivers to hit their heads.

The backup camera shows a blank blue screen when shifted into reverse, often with a "Service Rear Vision System" message. Reports cluster between about 50,000 and 88,000 miles. Owners and dealers tie the problem to Technical Service Bulletin 19-NA-076 and call it common on GM vehicles. One driver backed into a telephone pole at 3 mph with the camera out, shattering the rear window. Several owners have not had it repaired.

Pulling away from a stop, the wheel jerks sharply opposite the direction of the turn. Power assist can also cut out mid-turn, with ESC and service parking brake messages appearing intermittently. In one diagnosed case the steering gear was losing voltage and needed replacement at an estimated $2035.63. Other filings describe a hard brake pedal from vacuum pump failure, plus forward automatic braking and lane departure warning that don't work while the dealer finds no codes.

Warning lights for stability control, ABS, and traction control come on together with a flashing check engine light and a stored P0300 misfire code. In one case it kept recurring after a dealer update and ended in a tow. One crash report describes the car lurching forward in stop-and-go traffic while the brake pedal failed to respond, hitting the vehicle ahead. Another describes the navigation and infotainment screen shutting off with an SD card error. With only 3 complaints, there is no clear pattern.

Rear differential binding is blamed for one crash. The other complaint actually describes the transmission sticking when shifting into Drive or Reverse, then slamming into gear hard enough to throw the driver toward the wheel. With only two filings, neither forms a clear pattern. Both describe sudden drivetrain behavior that can surprise the driver at low speed.

Both complaints involve crashes with injuries, and they describe opposite failures. In one side impact the air bags deployed, but metal fragments struck the driver's face and caused severe injuries. In the other, the driver-side air bags did not deploy when the vehicle was hit on that side. Two reports are too few to show a pattern, but each describes a serious occupant-protection failure.