Certified Benz & Beemer Compares 2014 Mercedes Benz M-Class VS 2014 Lexus RX Near Scottsdale, AZ

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2014 Mercedes Benz M-Class

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VS

2014 Lexus RX

Safety Comparison

An active infrared night vision system optional on the M-Class helps the driver to more easily detect people, animals or other objects in front of the vehicle at night. Using an infrared camera and near-infrared lights to detect heat, the system then displays the image on a monitor in the dashboard. The RX Series doesn’t offer a night vision system.

The M-Class’ optional 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. The RX Series doesn’t offer a lane departure warning system.

The M-Class’ 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 RX Series doesn’t offer a driver alert monitor.

Both the M-Class and the RX Series have standard driver and passenger frontal airbags, front side-impact airbags, driver knee airbags, side-impact head airbags, front and rear seatbelt pretensioners, height-adjustable front shoulder belts, plastic fuel tanks, traction control, electronic stability systems to prevent skidding and available all wheel drive.

The National Highway Traffic Safety Administration does 35 MPH front crash tests on new vehicles. In this test, results indicate that the Mercedes M-Class is safer than the Lexus RX Series:

M-Class

RX Series

OVERALL STARS

5 Stars

4 Stars

Driver

STARS

5 Stars

4 Stars

Neck Injury Risk

25%

43%

Neck Compression

28 lbs.

75 lbs.

Leg Forces (l/r)

380/346 lbs.

341/436 lbs.

Passenger

STARS

5 Stars

4 Stars

Chest Compression

.5 inches

.7 inches

Neck Injury Risk

35%

50%

Neck Stress

154 lbs.

205 lbs.

Leg Forces (l/r)

325/371 lbs.

312/397 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 and into a post at 20 MPH, results indicate that the Mercedes M-Class is safer than the Lexus RX Series:

M-Class

RX Series

Front Seat

STARS

5 Stars

5 Stars

HIC

41

88

Abdominal Force

150 G’s

166 G’s

Hip Force

256 lbs.

360 lbs.

Rear Seat

STARS

5 Stars

5 Stars

HIC

44

122

Spine Acceleration

29 G’s

40 G’s

Into Pole

STARS

5 Stars

5 Stars

Max Damage Depth

15 inches

20 inches

HIC

206

486

Spine Acceleration

29 G’s

39 G’s

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

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 RX Series has not been fully tested, yet.

The Mercedes M-Class has a better fatality history. The M-Class was involved in fatal accidents at a rate 4.8% lower per vehicle registered than the RX Series, according to the Insurance Institute for Highway Safety.

Warranty Comparison

There are over 58 percent more Mercedes dealers than there are Lexus dealers, which makes it much easier should you ever need service under the M-Class’ warranty.

Engine Comparison

The ML350’s standard 3.5 DOHC V6 produces 32 more horsepower (302 vs. 270) and 25 lbs.-ft. more torque (273 vs. 248) than the RX 350’s standard 3.5 DOHC V6. The ML350’s 3.5 DOHC V6 produces 7 more horsepower (302 vs. 295) than the RX 450h’s standard 3.5 DOHC V6 hybrid. The ML550’s standard 4.7 turbo V8 produces 107 more horsepower (402 vs. 295) than the RX 450h’s standard 3.5 DOHC V6 hybrid.

The M-Class’ 3.0 turbo V6 diesel produces 207 lbs.-ft. more torque (455 vs. 248) than the RX 350’s standard 3.5 DOHC V6.

As tested in Motor Trend the ML350 is faster than the Lexus RX Series:

M-Class

RX 350

RX 450h

Zero to 60 MPH

6.6 sec

6.8 sec

6.9 sec

Quarter Mile

15 sec

15.3 sec

15.2 sec

Speed in 1/4 Mile

92.9 MPH

91.4 MPH

92.6 MPH

Fuel Economy and Range Comparison

The M-Class has 7.4 gallons more fuel capacity than the RX Series Hybrid’s standard fuel tank (24.6 vs. 17.2 gallons), for longer range between fill-ups. The M-Class has 5.4 gallons more fuel capacity than the RX Series’ standard fuel tank (24.6 vs. 19.2 gallons).

Brakes and Stopping Comparison

For better stopping power the ML550’s brake rotors are larger than those on the RX Series:

ML350

ML550

RX Series

Front Rotors

13 inches

14.8 inches

12.9 inches

Rear Rotors

12.8 inches

13 inches

12.2 inches

The M-Class stops much shorter than the RX Series:

M-Class

RX Series

60 to 0 MPH

121 feet

138 feet

Motor Trend

Tires and Wheels Comparison

For better traction, the M-Class has larger standard tires than the RX Series (255/50R19 vs. 235/60R18). The M-Class’ optional tires are larger than the largest tires available on the RX Series (265/45R20 vs. 235/60R18).

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 RX Series’ standard 60 series tires. The M-Class’ optional tires have a lower 45 series profile than the RX Series’ optional 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 RX Series. The M-Class’ optional 20-inch wheels are larger than the 19-inch wheels optional on the RX Series.

Suspension and Handling Comparison

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 RX Series doesn’t offer an active sway bar system.

The M-Class has a standard continuously variable suspension system. Using sensors on steering angle, speed and other driver inputs, the shocks soften to improve ride, or stiffen when appropriate to aid handling on tricky roads or off-road. The RX Series’ suspension doesn’t offer adjustable shock absorbers.

The M-Class has a standard automatic load leveling suspension to keep ride height level with a heavy load or when towing. The RX Series doesn’t offer a load leveling suspension.

For a smoother ride and more stable handling, the M-Class’ wheelbase is 6.9 inches longer than on the RX Series (114.8 inches vs. 107.9 inches).

For better handling and stability, the track (width between the wheels) on the M-Class is .7 inches wider in the front and 1.8 inches wider in the rear than on the RX Series.

The ML350 BlueTEC 4MATIC handles at .81 G’s, while the RX 350 AWD pulls only .76 G’s of cornering force in a Car and Driver skidpad test.

The ML350 BlueTEC 4MATIC executes Motor Trend’s “Figure Eight” maneuver 1.7 seconds quicker than the RX 450h AWD (27 seconds @ .65 average G’s vs. 28.7 seconds @ .57 average G’s).

For greater off-road capability the M-Class Airmatic has a 3.9 inches greater minimum ground clearance than the RX 350 (11.2 vs. 7.3 inches), allowing the M-Class to travel over rougher terrain without being stopped or damaged.

Chassis Comparison

As tested by Car and Driver, the interior of the ML350 BlueTEC 4MATIC is quieter than the RX 350 AWD:

M-Class

RX Series

At idle

42 dB

42 dB

Full-Throttle

69 dB

73 dB

70 MPH Cruising

67 dB

70 dB

Passenger Space Comparison

The M-Class has .6 inches more front shoulder room, .8 inches more rear headroom, 1.6 inches more rear legroom and .9 inches more rear shoulder room than the RX Series.

Cargo Capacity Comparison

A low lift-over cargo hatch design makes loading and unloading the M-Class easier. The M-Class’ cargo hatch lift-over height is 29 inches, while the RX Series’ liftover is 30.9 inches.

Ergonomics Comparison

The M-Class’ 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 RX Series’ standard manually variable intermittent wipers have to be constantly adjusted.

While driving with high beams on, sensitive light sensors available for the M-Class detect other vehicles which could be blinded and automatically switch to low beams. The RX Series doesn’t offer automatic dimming high beams.

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 RX Series doesn’t offer secondary sun visors.

The M-Class has standard heated front seats. Heated front seats cost extra on the RX Series. The M-Class also offers optional heated rear seats to keep those passengers extremely comfortable in the winter. Heated rear seats aren’t available in the RX Series.

The M-Class’ optional Active Parking Assist can parallel park or back into a parking spot by itself, with the driver only controlling speed with the brake pedal. The RX Series doesn’t offer an automated parking system.

Economic Advantages Comparison

According to The Car Book by Jack Gillis, the M-Class is less expensive to operate than the RX Series because typical repairs cost less on the M-Class than the RX Series, including $148 less for a water pump, $73 less for an alternator, $42 less for front brake pads, $115 less for fuel injection, $43 less for a fuel pump, $184 less for a timing belt/chain and $122 less for a power steering pump.

Recommendations Comparison

Strategic Vision rates overall owner satisfaction with vehicle quality. With a Total Quality Index of 906, Strategic Vision rated the Mercedes M-Class 31 points higher than the Lexus RX Series for 2012.

The Mercedes M-Class outsold the Lexus RX Series by 78% during 2013.

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