For enhanced safety, the front and rear seat shoulder belts of the Mercedes GLC Coupe have pretensioners to tighten the seatbelts and eliminate dangerous slack in the event of a collision and force limiters to limit the pressure the belts will exert on the passengers. The GMC Terrain doesn’t offer pretensioners for its rear seat belts.
The GLC Coupe’s pre-crash front seatbelts will tighten automatically in the event the vehicle detects an impending crash, improving protection against injury significantly. The Terrain doesn’t offer pre-crash pretensioners.
For enhanced safety, the front seat shoulder belts of the Mercedes GLC Coupe are height-adjustable to accommodate a wide variety of driver and passenger heights. A better fit can prevent injuries and the increased comfort also encourages passengers to buckle up. The GMC Terrain doesn’t offer height-adjustable seat belts.
The Mercedes GLC Coupe has a standard driver’s side knee airbag mounted low on the dashboard. The knee airbag helps prevent the driver from sliding under the seatbelts or the main frontal airbag; this keeps the driver better positioned during a collision for maximum protection. A knee airbag also helps keep the legs from striking the dashboard, preventing knee and leg injuries in the case of a serious frontal collision. The Terrain doesn’t offer knee airbags.
The GLC Coupe has standard NECK-PRO front head restraints, which use a specially designed headrest to protect the driver and front passenger from whiplash. During a rear-end collision, the NECK-PRO front head restraints system moves the headrests forward to prevent neck and spine injuries. The Terrain doesn’t offer a whiplash protection system.
Over 200 people are killed each year when backed over by motor vehicles. The GLC Coupe has a standard Maneuvering Brake Function that uses rear sensors to monitor for objects to the rear and automatically applies the brakes to prevent a collision. The Terrain doesn’t offer backup collision prevention brakes.
To provide maximum traction and stability on all roads, All-Wheel Drive is standard on the GLC Coupe. But it costs extra on the Terrain.
Earlier warning of stopped traffic, traffic signals, dangerous road conditions, weather, or accidents, can keep driver's safer and prevent crashes. The GLC Coupe has Car-to-X Communication, a system that seamlessly communicates important warnings to the driver about impending danger, if they're available. The Terrain doesn’t offer a system that can receive automated systems from infrastructure or other vehicles.
The GLC Coupe has a standard blind spot warning system that uses sensors to alert the driver to objects in the vehicle’s blind spots where the side view mirrors don’t reveal them. A system to reveal vehicles in the Terrain’s blind spot costs extra.
To help make backing out of a parking space safer, the GLC Coupe has standard Rear Cross-Traffic Alert and Active Brake Assist automatically engages the brakes to help avoid a collision. GMC charges extra for Rear Cross Traffic Alert on the Terrain and the Terrain’s Rear Cross Traffic Alert does not include automatic braking.
The GLC Coupe’s driver alert monitor detects an inattentive driver then sounds a warning and suggests a break. According to the NHTSA, drivers who fall asleep cause about 100,000 crashes and 1500 deaths a year. The Terrain doesn’t offer a driver alert monitor.
Both the GLC Coupe and the Terrain have standard driver and passenger frontal airbags, front side-impact airbags, side-impact head airbags, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, rearview cameras and available lane departure warning systems.
The Mercedes GLC Coupe weighs 593 to 869 pounds more than the GMC Terrain. The NHTSA advises that heavier vehicles are much safer in collisions than their significantly lighter counterparts.