Son's Automotive Group Compares 2018 BMW X5 VS 2018 Acura MDX Near Norcross, GA

Responsive image

2018 BMW X5

Responsive image

2018 BMW X5

Responsive image

2018 Acura MDX

Safety Comparison

The X5 has standard Active Head Restraints, which use a specially designed headrest to protect the driver and front passenger from whiplash. During a rear-end collision, the Active Head Restraints system moves the headrests forward to prevent neck and spine injuries. The MDX doesn’t offer a whiplash protection system.

A passive infrared night vision system optional on the X5 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 MDX doesn’t offer a night vision system.

The X5’s optional driver alert monitor detects an inattentive driver then sounds a warning and suggests a break. According to the NHTSA, drivers who fall asleep cause about 100,000 crashes and 1500 deaths a year. The MDX doesn’t offer a driver alert monitor.

Both the X5 and the MDX have standard driver and passenger frontal airbags, front side-impact airbags, driver knee airbags, side-impact head airbags, front seatbelt pretensioners, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, daytime running lights, rearview cameras, available all-wheel drive, crash mitigating brakes, lane departure warning systems, blind spot warning systems and around view monitors.

The National Highway Traffic Safety Administration does 35 MPH front crash tests on new vehicles. In this test, results indicate that the BMW X5 is safer than the Acura MDX:







5 Stars

5 Stars




Neck Stress

155 lbs.

177 lbs.

Neck Compression

23 lbs.

113 lbs.

Leg Forces (l/r)

470/286 lbs.

467/511 lbs.

New test not comparable to pre-2011 test results. More stars = Better. Lower test results = Better.

The National Highway Traffic Safety Administration does side impact tests on new vehicles. In this test, which crashes the vehicle into a flat barrier at 38.5 MPH, results indicate that the BMW X5 is safer than the Acura MDX:





Front Seat


5 Stars

5 Stars




Chest Movement

.5 inches

.6 inches

Hip Force

202 lbs.

244 lbs.


Rear Seat


5 Stars

5 Stars




Spine Acceleration

42 G’s

52 G’s

Hip Force

685 lbs.

757 lbs.

New test not comparable to pre-2011 test results. More stars = Better. Lower test results = Better.

Warranty Comparison

The X5’s corrosion warranty is 7 years longer than the MDX’s (12 vs. 5 years).

BMW pays for scheduled maintenance on the X5 for 3 years and 36,000 miles. BMW will pay for oil changes, lubrication and any other required maintenance. Acura doesn’t pay scheduled maintenance for the MDX.

There are over 25 percent more BMW dealers than there are Acura dealers, which makes it easier should you ever need service under the X5’s warranty.

Reliability Comparison

The camshafts in the X5’s engine are driven by a hardened steel chain, with no maintenance needs. The MDX’s camshafts are driven by a rubber belt that needs periodic replacement. If the MDX’s cam drive belt breaks the engine could be severely damaged when the pistons hit the opened valves.

To reliably power the ignition and other systems and to recharge the battery, the X5 has a standard 210-amp alternator. The MDX’s 150-amp alternator isn’t as powerful.

The battery on the X5 is in the trunk, which protects it from hot underhood temperatures that can degrade battery life. By keeping the X5’s battery 20 to 30 degrees cooler, its life is increased by years. The MDX’s battery is in the hot engine compartment.

J.D. Power and Associates rated the X5 second among midsize premium suvs in their 2017 Initial Quality Study. The MDX isn’t in the top three.

J.D. Power and Associates’ 2017 Initial Quality Study of new car owners surveyed provide the statistics that show that BMW vehicles are better in initial quality than Acura vehicles. J.D. Power ranks BMW 6th in initial quality, above the industry average. With 15 more problems per 100 vehicles, Acura is ranked 19th, below the industry average.

From surveys of all its subscribers, Consumer Reports’ April 2017 Auto Issue reports that BMW vehicles are more reliable than Acura vehicles. Consumer Reports ranks BMW 4 places higher in reliability than Acura.

Engine Comparison

The X5 s/xDrive35i’s standard 3.0 turbo 6 cyl. produces 10 more horsepower (300 vs. 290) and 33 lbs.-ft. more torque (300 vs. 267) than the MDX’s standard 3.5 SOHC V6. The X5 s/xDrive35i’s 3.0 turbo 6 cyl. produces 11 lbs.-ft. more torque (300 vs. 289) than the MDX Sport Hybrid’s standard 3.0 SOHC V6 hybrid. The X5 xDrive50i’s standard 4.4 turbo V8 produces 124 more horsepower (445 vs. 321) and 191 lbs.-ft. more torque (480 vs. 289) than the MDX Sport Hybrid’s standard 3.0 SOHC V6 hybrid.

The X5’s 3.0 turbo diesel produces 146 lbs.-ft. more torque (413 vs. 267) than the MDX’s standard 3.5 SOHC V6. The X5’s 3.0 turbo diesel produces 124 lbs.-ft. more torque (413 vs. 289) than the MDX Sport Hybrid’s standard 3.0 SOHC V6 hybrid.

As tested in Motor Trend the X5 s/xDrive35i 3.0 turbo 6 cyl. is faster than the Acura MDX V6:




Zero to 60 MPH

5.9 sec

6.2 sec

Quarter Mile

14.5 sec

14.7 sec

Speed in 1/4 Mile

95.1 MPH

94.6 MPH

Fuel Economy and Range Comparison

Regardless of its engine, regenerative brakes improve the X5’s fuel efficiency by converting inertia back into energy instead of wasting it. Acura only offers a regenerative brake system on the MDX Sport Hybrid.

The X5 has 3 gallons more fuel capacity than the MDX Sport Hybrid’s standard fuel tank (22.4 vs. 19.4 gallons), for longer range between fill-ups. The X5 has 2.9 gallons more fuel capacity than the MDX’s standard fuel tank (22.4 vs. 19.5 gallons).

Brakes and Stopping Comparison

For better stopping power the X5’s front brake rotors are larger than those on the MDX:



X5 xDrive50i


MDX Sport Hybrid

Front Rotors

13.1 inches

14.4 inches

12.6 inches

13 inches

Rear Rotors

12.6 inches

13.6 inches

13 inches

13 inches

The X5’s standard front and rear disc brakes are vented to help dissipate heat for shorter stops with less fading. The rear discs on the MDX are solid, not vented.

The X5 stops much shorter than the MDX:





70 to 0 MPH

178 feet

185 feet

Car and Driver

60 to 0 MPH

110 feet

121 feet

Motor Trend

Tires and Wheels Comparison

For better traction, the X5 has larger standard tires than the MDX (255/50R19 vs. 245/60R18). The X5’s optional tires are larger than the largest tires available on the MDX (F:275/40R20 & R:315/35R20 vs. 245/60R18).

The X5’s standard tires provide better handling because they have a lower 50 series profile (height to width ratio) that provides a stiffer sidewall than the MDX’s standard 60 series tires. The X5’s optional 275/40R20 front and 315/35R20 rear tires have a lower 40 series front and 35 series rear profile than the MDX’s optional 50 series tires.

For better ride, handling and brake cooling the X5 has standard 19-inch wheels. Smaller 18-inch wheels are standard on the MDX.

Changing a flat tire near traffic can be dangerous and inconvenient. The run-flat tires available on the X5 can be driven up to 50 miles without any air pressure, allowing you to drive to a service station for a repair. The MDX doesn’t offer run-flat tires.

Suspension and Handling Comparison

The X5 offers an available adjustable active suspension system, which counteracts cornering forces actively, limiting body roll and improving handling and stability. Acura doesn’t offer an active suspension on the MDX.

The X5 has a standard automatic rear load leveling suspension to keep ride height level with a heavy load or when towing. The MDX doesn’t offer a load leveling suspension.

For a smoother ride and more stable handling, the X5’s wheelbase is 4.5 inches longer than on the MDX (115.5 inches vs. 111 inches).

The X5’s front to rear weight distribution is more even (50% to 50%) than the MDX’s (57% to 43%). This gives the X5 more stable handling and braking.

The X5 xDrive50i xDrive executes Motor Trend’s “Figure Eight” maneuver quicker than the MDX SH-AWD (26.3 seconds @ .72 average G’s vs. 27 seconds @ .65 average G’s).

For greater off-road capability the X5 has a greater minimum ground clearance than the MDX (8.2 vs. 7.3 inches), allowing the X5 to travel over rougher terrain without being stopped or damaged.

Chassis Comparison

The X5 is 3 inches shorter than the MDX, making the X5 easier to handle, maneuver and park in tight spaces.

As tested by Car and Driver while under full throttle, the interior of the X5 xDrive35i xDrive is quieter than the MDX SH-AWD (73 vs. 76 dB).

Cargo Capacity Comparison

The X5’s rear cargo window opens separately from the rest of the tailgate door to allow quicker loading of small packages. The MDX’s rear cargo window doesn’t open.

Ergonomics Comparison

Unlike the driver-only memory system in the MDX, the X5 xDrive50i has a passenger memory, so that when drivers switch, the memory setting adjusts the driver’s seat, steering wheel position, outside mirror angle, climate settings and radio stations and the front passenger seat also adjusts to the new passenger’s preset preferences.

The power windows standard on both the X5 and the MDX have locks to prevent small children from operating them. When the lock on the X5 is engaged the driver can still operate all of the windows, for instance to close one opened by a child. The MDX prevents the driver from operating the other windows just as it does the other passengers.

The X5’s rain-sensitive wipers adjust their speed and turn on and off automatically based on the amount of rainfall on the windshield. This allows the driver to concentrate on driving without constantly adjusting the wipers. The MDX’s standard intermittent wipers change speed with vehicle speed, but can’t turn on and off or change speed based on changing rainfall.

Heated windshield washer nozzles are standard on the X5 to prevent washer fluid and nozzles from freezing and help continue to keep the windshield clear in sub-freezing temperatures. The MDX doesn’t offer heated windshield washer nozzles.

In poor weather, headlights can lose their effectiveness as grime builds up on their lenses. This can reduce visibility without the driver realizing. The X5 offers available headlight washers to keep headlight output high. The MDX doesn’t offer headlight washers.

To help drivers avoid possible obstacles, the X5 has standard cornering lights to illuminate around corners when the turn signals are activated. The MDX doesn’t offer cornering lights. The X5 also has standard adaptive headlights to illuminate around corners automatically by reading vehicle speed and steering wheel angle.

To shield the driver and front passenger’s vision over a larger portion of the windshield and side windows, the X5 has standard extendable sun visors. The MDX doesn’t offer extendable visors.

The X5’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 MDX doesn’t offer an automated parking system.

Economic Advantages Comparison

Insurance will cost less for the X5 owner. The Car Book by Jack Gillis rates the X5 with a number “3” insurance rate while the MDX is rated higher at a number “10” rate.

According to The Car Book by Jack Gillis, the X5 is less expensive to operate than the MDX because typical repairs cost much less on the X5 than the MDX, including $206 less for a power steering pump.

Recommendations Comparison

Consumer Reports® recommends both the BMW X5 and the Acura MDX, based on reliability, safety and performance.

J.D. Power and Associates rated the X5 third among midsize premium suvs in owner reported satisfaction. This includes how well the vehicle performs and satisfies its owner’s expectations. The MDX isn’t in the top three.

© 1991-2016 Advanta-STAR Automotive Research. All rights reserved. Who We Are
Click here to view the disclaimers, limitations and notices about EPA fuel mileage, crash tests, coprights, trademarks, and other issues.