For enhanced safety, the front and second-row seat shoulder belts of the Mercedes GLS 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 Jeep Grand Cherokee L doesn’t offer pretensioners for its second-row seat belts.
The GLS’ pre-crash front seatbelts will tighten automatically in the event the vehicle detects an impending crash, improving protection against injury significantly. The Grand Cherokee L doesn’t offer pre-crash pretensioners.
The GLS has a standard Post Collision Brake, which automatically applies the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The Grand Cherokee L doesn’t offer a post collision braking system: in the event of a collision that triggers the airbags, more collisions are possible without the protection of airbags that may have already deployed.
To provide maximum traction and stability on all roads, All-Wheel Drive is standard on the GLS. But it costs extra on the Grand Cherokee L.
Earlier warning of stopped traffic, traffic signals, dangerous road conditions, weather, or accidents, can keep driver's safer and prevent crashes. The GLS has Car-to-X Communication, a system that seamlessly communicates important warnings to the driver about impending danger, if they're available. The Grand Cherokee L doesn’t offer a system that can receive automated systems from infrastructure or other vehicles.
Both the GLS and Grand Cherokee L have rear cross-traffic warning, but the GLS has Active Brake Assist (automatically applies the brakes) to better prevent a collision when backing near traffic. The Grand Cherokee L’s Rear Cross Path Detection doesn’t automatically brake.
Both the GLS and the Grand Cherokee L have standard driver and passenger frontal airbags, front side-impact airbags, driver knee airbags, side-impact head airbags, height adjustable front shoulder belts, plastic fuel tanks, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, lane departure warning systems, blind spot warning systems, rearview cameras and rear cross-path warning.
The Mercedes GLS weighs 455 to 1696 pounds more than the Jeep Grand Cherokee L. The NHTSA advises that heavier vehicles are much safer in collisions than their significantly lighter counterparts.

