For enhanced safety, the front and rear seat shoulder belts of the Lexus IS 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 BMW 4 Series Gran Coupe doesn’t offer pretensioners for its rear seat belts.
For enhanced safety, the front seat shoulder belts of the Lexus IS 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 BMW 4 Series Gran Coupe doesn’t offer height-adjustable seat belts.
Over 200 people are killed each year when backed over by motor vehicles. The IS offers optional Intuitive Parking Assist with Auto Braking that uses rear sensors to monitor for objects to the rear and automatically applies the brakes to prevent a collision. The 4 Series Gran Coupe doesn’t offer backup collision prevention brakes.
Both the IS and 4 Series Gran Coupe have rear cross-traffic warning, but the IS offers optional Rear Cross-Traffic Braking (automatically applies the brakes) to better prevent a collision when backing near traffic. The 4 Series Gran Coupe’s Cross Traffic Warning doesn’t automatically brake.
Both the IS and the 4 Series Gran Coupe have standard driver and passenger frontal airbags, front side-impact airbags, driver and front passenger knee airbags, side-impact head airbags, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, post-collision automatic braking systems, daytime running lights, lane departure warning systems, blind spot warning systems, rearview cameras, rear cross-path warning, available all wheel drive and around view monitors.
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 standard headlight’s “Good” rating, the Insurance Institute for Highway Safety grants the IS its highest rating: “Top Safety Pick Plus” for 2022, a rating granted to only 126 vehicles tested by the IIHS. The 4 Series Gran Coupe has not been tested, yet.