The X5 M offers optional City Collision Mitigation, which use forward mounted sensors to warn the driver of a possible collision ahead. If the driver doesn’t react and the system determines a collision is imminent, it automatically applies the brakes at full-force in order to reduce the force of the crash or avoid it altogether. The G-Class doesn't offer collision warning or crash mitigation brakes.
When descending a steep, off-road slope, the X5 M’s standard Hill Descent Control allows you to creep down safely. The G-Class doesn’t offer Hill Descent Control.
A passive infrared night vision system optional on the X5 M helps the driver to more easily detect people, animals or other objects in front of the vehicle at night. Using an infrared camera to detect heat, the system then displays the image on a monitor in the dashboard. The G-Class doesn’t offer a night vision system.
The X5 M’s optional lane departure warning system alerts a temporarily inattentive driver when the vehicle begins to leave its lane. The G-Class doesn’t offer a lane departure warning system.
The X5 M offers an optional Side and Top View Cameras to allow the driver to see objects all around the vehicle on a screen. The G-Class only offers a rear monitor and front and rear parking sensors that beep. That doesn’t help with obstacles to the sides.
For better protection of the passenger compartment, the X5 M uses safety cell construction with a three-dimensional high-strength frame that surrounds the passenger compartment. It provides extra impact protection and a sturdy mounting location for door hardware and side impact beams. The G-Class uses a body-on-frame design, which has no frame members above the floor of the vehicle.
Both the X5 M and the G-Class have standard driver and passenger frontal airbags, side-impact head airbags, front seatbelt pretensioners, four-wheel antilock brakes, all wheel drive, traction control, electronic stability systems to prevent skidding, daytime running lights, rearview cameras and available blind spot warning systems.
The X5 M’s corrosion warranty is 8 years and unlimited miles longer than the G-Class’ (12/unlimited vs. 4/50,000).
BMW pays for scheduled maintenance on the X5 M for 4 years and 50,000 miles. BMW will pay for oil changes, lubrication and any other required maintenance. Mercedes doesn’t pay scheduled maintenance for the G-Class.
There are over 12 percent more BMW dealers than there are Mercedes dealers, which makes it easier should you ever need service under the X5 M’s warranty.
To reliably power the ignition and other systems and to recharge the battery, the X5 M has a standard 209-amp alternator. The G-Class’ 180-amp alternator isn’t as powerful.
J.D. Power and Associates’ 2015 Initial Quality Study of new car owners surveyed provide the statistics that show that BMW vehicles are better in initial quality than Mercedes vehicles. J.D. Power ranks BMW 6th in initial quality, above the industry average. With 12 more problems per 100 vehicles, Mercedes is ranked 14th.
The X5 M’s 4.4 turbo V8 produces 151 more horsepower (567 vs. 416) and 3 lbs.-ft. more torque (553 vs. 550) than the G550’s standard 4.0 turbo V8. The X5 M’s 4.4 turbo V8 produces 4 more horsepower (567 vs. 563) than the G63’s standard 5.5 turbo V8.
On the EPA test cycle the X5 M gets better fuel mileage than the G63 AMG (14 city/19 hwy vs. 12 city/14 hwy). The X5 M gets better fuel mileage than the G65 AMG (14 city/19 hwy vs. 11 city/13 hwy).
Regenerative brakes improve the X5 M’s fuel efficiency by converting inertia back into energy instead of wasting it. The G-Class doesn’t offer a regenerative braking system.
For better stopping power the X5 M’s brake rotors are larger than those on the G-Class:
The X5 M’s standard front and rear disc brakes are vented to help dissipate heat for shorter stops with less fading. The rear discs standard on the G550 are solid, not vented.
For better traction, the X5 M has larger tires than the G-Class (F:285/35R21 & R:325/30R21 vs. 275/55R19).
The X5 M’s standard 285/40R20 front and 325/35R20 rear tires provide better handling because they have a lower 40 series front and 35 series rear profile (height to width ratio) that provides a stiffer sidewall than the G550’s standard 55 series tires. The X5 M’s 285/35R21 front and 325/30R21 rear tires have a lower 35 series front and 30 series rear profile than the G65’s 45 series tires.
For better ride, handling and brake cooling the X5 M has standard 20-inch wheels. Smaller 19-inch wheels are standard on the G550.
The BMW X5 M’s independent front suspension is much lighter than the Mercedes G-Class’ solid front axle, which allows the X5 M’s wheels to react more quickly and accurately to the road’s surface, improving both ride and handling.
For superior ride and handling, the BMW X5 M has fully independent front and rear suspensions. An independent suspension allows the wheels to follow the road at the best angle for gripping the pavement, without compromising ride comfort. The Mercedes G-Class has a solid rear axle, with a non-independent rear suspension.
The X5 M has standard front and rear stabilizer bars, which help keep the X5 M flat and controlled during cornering. The G-Class’ suspension doesn’t offer a rear stabilizer bar.
The rear suspension of the X5 M uses air springs for a smoother, controlled ride than the G-Class, which uses coil springs. Air springs maintain proper ride height and ride more smoothly.
The X5 M offers an available adjustable active suspension system, which counteracts cornering forces actively, limiting body roll and improving handling and stability. Mercedes doesn’t offer an active suspension on the G-Class.
The X5 M has a standard automatic rear load leveling suspension to keep ride height level with a heavy load or when towing. The G-Class doesn’t offer a load leveling suspension.
For much better steering response and tighter handling the X5 M has rack and pinion steering, like Formula race cars, instead of the recirculating-ball type steering of the G-Class.
The X5 M has vehicle speed sensitive variable-assist power steering, for low-effort parking, better control at highway speeds and during hard cornering, and a better feel of the road. The G-Class doesn’t offer variable-assist power steering.
For a smoother ride and more stable handling, the X5 M’s wheelbase is 3.3 inches longer than on the G-Class (115.5 inches vs. 112.2 inches).
For better handling and stability, the track (width between the wheels) on the X5 M is 6 inches wider in the front and 6 inches wider in the rear than on the G-Class.
For better maneuverability, the X5 M’s turning circle is 2.6 feet tighter than the G-Class’ (42 feet vs. 44.6 feet).
The BMW X5 M may be more efficient, handle and accelerate better because it weighs about 550 to 650 pounds less than the Mercedes G-Class.
The X5 M is 8.7 inches shorter in height than the G-Class, making the X5 M much easier to wash and garage and drive (lower center of gravity).
Unibody construction makes the X5 M’s chassis much stiffer, which contributes to better handling, and enables softer springs to be used for a better ride. Unibody construction’s stiffness also contributes to better durability and less body squeaks and rattles. The G-Class doesn’t use unibody construction, but a body-on-frame design.
The design of the BMW X5 M amounts to more than styling. The X5 M has an aerodynamic coefficient of drag of .38 Cd. That is significantly lower than the G-Class (.54). A more efficient exterior helps keep the interior quieter and helps the X5 M get better fuel mileage.
For excellent aerodynamics, the X5 M has standard flush composite headlights. The G-Class has recessed headlights that spoil its aerodynamic shape and create extra drag.
The X5 M offers optional seating for 7 passengers; the G-Class can only carry 5.
The X5 M has 7.8 inches more front shoulder room and 3.7 inches more rear shoulder room than the G-Class.
The X5 M’s rear cargo window opens separately from the rest of the tailgate door to allow quicker loading of small packages. The G-Class’ rear cargo window doesn’t open.
To make loading and unloading groceries and cargo easier, especially for short adults or children, the X5 M has a standard power cargo door, which opens and closes automatically by pressing a button. The G-Class doesn’t offer a power cargo door.
The X5 M offers an optional heads-up display which projects speed and other key instrumentation readouts in front of the driver’s line of sight, allowing drivers to view information without diverting their eyes from the road. The G-Class doesn’t offer a heads-up display.
The X5 M’s front and rear power windows all open or close with one touch of the switches, making it more convenient at drive-up windows and toll booths, or when talking with someone outside of the car. The G-Class’ power windows’ switches have to be held the entire time to close them fully.
If the windows are left down on the X5 M the driver can raise them all using the key in the outside lock cylinder. On a hot day the driver can lower the windows from outside the vehicle using the key in the outside lock cylinder or the keyless remote. The driver of the G-Class can only raise the windows from inside the vehicle, with the ignition on.
Comfort Access standard on the X5 M allows you to unlock the driver’s door, cargo door and start the engine all without removing a key from pocket or purse. This eliminates searching for keys before loading groceries, getting in the vehicle in bad weather or making a hurried start to your trip. The Mercedes G-Class doesn’t offer an advanced key system.
To improve rear visibility by keeping the rear window clear, the X5 M has a standard rear variable intermittent wiper with a full on position. The rear wiper standard on the G-Class only has an intermittent setting, so in a hard rain visibility isn’t as good.
While driving with high beams on, sensitive light sensors available for the X5 M detect other vehicles which could be blinded and automatically switch to low beams. The G-Class doesn’t offer automatic dimming high beams.
The G-Class’ cornering lamps activate a lamp on the front corner when the turn signal is activated. The X5 M’s standard adaptive cornering lights turn the actual headlight unit up to several degrees, depending on steering wheel angle and vehicle speed. This lights a significant distance into corners at any speed.
To shield the driver and front passenger’s vision over a larger portion of the windshield and side windows, the X5 M has standard extendable sun visors. The G-Class doesn’t offer extendable visors.
The X5 M has a standard center folding armrest for the middle row passengers. A center armrest helps make middle row passengers more comfortable. The G-Class doesn’t offer a rear seat center armrest.
The X5 M’s optional Parking Assistant can parallel park or back into a parking spot by itself, with the driver only controlling speed with the brake pedal. The G-Class doesn’t offer an automated parking system.
Insurance will cost less for the X5 M owner. The Complete Car Cost Guide estimates that insurance for the X5 M will cost $2640 to $3695 less than the G-Class over a five-year period.
Intellichoice estimates that five-year ownership costs (depreciation, financing, insurance, fuel, fees, repairs and maintenance) for the BMW X5 M will be $15486 to $30798 less than for the Mercedes G-Class.