For enhanced safety, the front seat shoulder belts of the Infiniti QX55 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 Mercedes GLA doesn’t offer height-adjustable seat belts.
The Infiniti QX55 has standard driver and front passenger side knee airbags mounted low on the dashboard. These airbags helps prevent the driver and front passenger from sliding under their seatbelts or the main frontal airbags; this keeps them better positioned during a collision for maximum protection. Knee airbags also help keep the legs from striking the dashboard, preventing knee and leg injuries in the case of a serious frontal collision. The GLA doesn’t offer a front passenger side knee airbag.
Over 200 people are killed each year when backed over by motor vehicles. The QX55 has standard Rear Automatic Braking that uses rear sensors to monitor and automatically apply the brakes to prevent a rear collision. The GLA doesn’t offer backup collision prevention brakes.
To provide maximum traction and stability on all roads, All-Wheel Drive is standard on the QX55. But it costs extra on the GLA.
The QX55’s standard lane departure warning system alerts a temporarily inattentive driver when the vehicle begins to leave its lane and gently nudges the vehicle back towards its lane. A lane departure warning system costs extra on the GLA.
Both the QX55 and the GLA have standard driver and passenger frontal airbags, front side-impact airbags, driver knee airbags, side-impact head airbags, front and rear seatbelt pretensioners, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, blind spot warning systems, rearview cameras, rear cross-path warning and available around view monitors.
The Infiniti QX55 weighs 576 to 739 pounds more than the Mercedes GLA. The NHTSA advises that heavier vehicles are much safer in collisions than their significantly lighter counterparts.