For enhanced safety, the front and rear seat shoulder belts of the Lexus UX 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 Alfa Romeo Stelvio doesn’t offer pretensioners for the rear seat belts.
Using vehicle speed sensors and seat sensors, smart airbags in the UX deploy with different levels of force or don’t deploy at all to help better protect passengers of all sizes in different collisions. The UX’s side airbags will shut off if a child is leaning against the door. The Stelvio’s airbags don’t have smart features and will always deploy full force.
The UX has standard Whiplash Injury Lessening Front Seatbacks, which use a specially designed seat to protect the driver and front passenger from whiplash. During a rear-end collision, the Whiplash Injury Lessening Front Seatbacks system allows the backrest to travel backwards to cushion the occupants and the headrests move forward to prevent neck and spine injuries. The Stelvio doesn’t offer a whiplash protection system.
The UX has a standard Secondary Collision Brake, which automatically applies the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The Stelvio 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.
Over 200 people are killed each year when backed over by motor vehicles. The UX offers optional Parking Support Brake that uses rear sensors to monitor and automatically apply the brakes to prevent a rear collision. The Stelvio doesn’t offer backup collision prevention brakes.
The UX’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 Stelvio.
The UX has a standard blind spot warning system which uses sensors to alert the driver to objects in the vehicle’s blind spots where the side view mirrors don’t reveal them and moves the vehicle back into its lane. A system to reveal vehicles in the Stelvio’s blind spot costs extra.
To help make backing out of a parking space safer, the UX has a standard rear cross-path warning system, which uses sensors in the rear bumper to alert the driver to vehicles approaching from the side, helping the driver avoid collisions. Rear cross-path warning costs extra on the Stelvio.
Both the UX and the Stelvio have standard driver and passenger frontal airbags, front side-impact airbags, driver and front passenger 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, rearview cameras and available rear parking sensors.
For its top level performance in IIHS driver and passenger-side small overlap frontal, moderate overlap frontal, side impact, roof strength and head restraint tests, its standard vehicle-to-vehicle front crash prevention system, its standard vehicle-to-pedestrian front crash prevention system, and its available headlight’s “Good” rating, the Insurance Institute for Highway Safety grants the UX the rating of “Top Pick” for 2021, a rating granted to only 128 vehicles tested by the IIHS. The Stelvio has not been tested, yet.