For enhanced safety, the front and rear seat shoulder belts of the Mercedes M-Class 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 X5 doesn’t offer pretensioners for the rear seat belts.
The M-Class’ front seatbelts will tighten automatically in the event the vehicle detects an impending crash, improving protection against injury significantly. The X5 doesn’t offer pre-crash pretensioners.
For enhanced safety, the front seat shoulder belts of the Mercedes M-Class 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 X5 doesn’t offer height-adjustable seat belts.
Both the M-Class and the X5 have standard driver and passenger frontal airbags, side-impact head airbags, traction control, electronic stability systems to prevent skidding and available all wheel drive.
For its top level performance in all IIHS frontal, side, rear impact and roof-crush tests, and its standard front crash prevention system, the Insurance Institute for Highway Safety grants the M-Class its highest rating: “Top Pick Plus” for 2014, a rating granted to only 28 vehicles tested by the IIHS. The X5 has not been tested, yet.
J.D. Power and Associates’ 2013 Initial Quality Study of new car owners surveyed provide the statistics that show that Mercedes vehicles are better in initial quality than BMW vehicles. J.D. Power ranks Mercedes 11th in initial quality, above the industry average. With 8 more problems per 100 vehicles, BMW is ranked 18th, below the industry average.
J.D. Power and Associates’ 2013 survey of the owners of three-year-old vehicles provides the long-term dependability statistics that show that Mercedes vehicles are more reliable than BMW vehicles. J.D. Power ranks Mercedes fifth in reliability, above the industry average. With 18 more problems per 100 vehicles, BMW is ranked 16th.
The ML550’s standard 4.7 turbo V8 produces 102 more horsepower (402 vs. 300) and 148 lbs.-ft. more torque (443 vs. 295) than the X5 s/xDrive35i’s standard 3.0 turbo 6 cyl.
The M-Class’ 3.0 turbo V6 diesel produces 42 lbs.-ft. more torque (455 vs. 413) than the X5’s 3.0 turbo diesel.
The M-Class has 2.2 gallons more fuel capacity than the X5 (24.6 vs. 22.4 gallons), for longer range between fill-ups.
The M-Class’ standard tires provide better handling because they have a lower 50 series profile (height to width ratio) that provides a stiffer sidewall than the X5’s standard 55 series tires.
For better ride, handling and brake cooling the M-Class has standard 19-inch wheels. Smaller 18-inch wheels are standard on the X5.
The M-Class offers active sway bars, which help keep it flat and controlled during cornering, but disconnect at lower speeds to smooth the ride and offer greater off-road suspension articulation. This helps keep the tires glued to the road on-road and off. The X5 doesn’t offer an active sway bar system.
For better maneuverability, the M-Class’ turning circle is 3.1 feet tighter than the X5’s (38.7 feet vs. 41.8 feet).
For greater off-road capability the M-Class Airmatic has a 3 inches greater minimum ground clearance than the X5 (11.2 vs. 8.2 inches), allowing the M-Class to travel over rougher terrain without being stopped or damaged.
The M-Class is 4.1 inches shorter than the X5, making the M-Class easier to handle, maneuver and park in tight spaces.
The M-Class has 1.8 inches more rear legroom and .1 inches more rear shoulder room than the X5.
The M-Class has a much larger cargo area with its rear seat up than the X5 with its rear seat up (38.2 vs. 22.9 cubic feet). The M-Class has a much larger cargo area with its rear seat folded than the X5 with its rear seat folded (80.3 vs. 66 cubic feet).
The M-Class’ liftgate lifts up in one piece, completely out of the way of loading and unloading, while sheltering the cargo loading area. The X5’s tailgate’s top part raises up, but the bottom part lowers, getting in the way of loading and making an uneven surface for sliding cargo.
To better shield the driver and front passenger’s vision, the M-Class offers optional dual-element sun visors that can block glare from two directions simultaneously. The X5 doesn’t offer secondary sun visors.
The M-Class offers an optional 115 volt a/c outlet in the cargo area, allowing you to recharge a laptop or run small household appliances without special adapters which can break or get misplaced. The X5 doesn’t offer a house-current electrical outlet.
Insurance will cost less for the M-Class owner. The Complete Car Cost Guide estimates that insurance for the M-Class will cost $1405 to $3320 less than the X5 over a five-year period.
Intellichoice estimates that five-year ownership costs (depreciation, financing, insurance, fuel, fees, repairs and maintenance) for the Mercedes M-Class will be $1400 to $3013 less than for the BMW X5.
Consumer Reports® recommends the Mercedes M-Class, based on reliability, safety and performance.
The Mercedes M-Class outsold the BMW X5 by 1508 units during 2013.