2019 Mercedes CLS vs. 2018 Audi A6

Detailed Review, Specifications & Comparison

Your buying experience includes...

business_centerProfessional Staff
account_balanceSimple Financing
local_gas_stationFull Tank of Gas
local_car_washFree Car Wash

Safety

To help make backing safer, the CLS’ optional cross-path warning system uses wide-angle radar in the rear bumper to alert the driver to vehicles approaching from the side, helping the driver avoid collisions. The A6 doesn’t offer a cross-path warning system.

The CLS’ 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 A6 doesn’t offer a driver alert monitor.

The CLS has standard Mercedes-Benz Emergency Call, which uses a global positioning satellite (GPS) receiver and a cellular system to remotely unlock your doors if you lock your keys in, help track down your vehicle if it’s stolen or send emergency personnel to the scene if any airbags deploy. The A6 doesn’t offer a GPS response system, only a navigation computer with no live response for emergencies, so if you’re involved in an accident and you’re incapacitated help may not come as quickly.

Both the CLS and the A6 have standard driver and passenger frontal airbags, front side-impact airbags, driver knee airbags, side-impact head airbags, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, daytime running lights, rearview cameras, available all wheel drive, lane departure warning systems and around view monitors.

Warranty

There are over 26 percent more Mercedes dealers than there are Audi dealers, which makes it easier should you ever need service under the CLS’ warranty.

Reliability

J.D. Power and Associates’ 2018 Initial Quality Study of new car owners surveyed provide the statistics that show that Mercedes vehicles are better in initial quality than Audi vehicles. J.D. Power ranks Mercedes 14th in initial quality, above the industry average. With 13 more problems per 100 vehicles, Audi is ranked 25th, below the industry average.

Engine

The CLS 450’s standard 3.0 turbo 6 cyl. hybrid produces 110 more horsepower (362 vs. 252) and 96 lbs.-ft. more torque (369 vs. 273) than the A6 2.0T’s standard 2.0 turbo 4 cyl. The CLS 450’s 3.0 turbo 6 cyl. hybrid produces 22 more horsepower (362 vs. 340) and 44 lbs.-ft. more torque (369 vs. 325) than the A6 3.0T’s standard 3.0 supercharged V6. The AMG CLS 53’s standard 3.0 turbo 6 cyl. hybrid produces 89 more horsepower (429 vs. 340) and 59 lbs.-ft. more torque (384 vs. 325) than the A6 3.0T’s standard 3.0 supercharged V6.

As tested in Car and Driver the CLS 450 is faster than the A6 3.0T:

 

CLS

A6

Zero to 60 MPH

4.7 sec

5.4 sec

Zero to 100 MPH

11.5 sec

13.4 sec

5 to 60 MPH Rolling Start

5.6 sec

5.9 sec

Quarter Mile

13.2 sec

13.9 sec

Speed in 1/4 Mile

107 MPH

102 MPH

Fuel Economy and Range

On the EPA test cycle the CLS gets better fuel mileage than the A6:

 

 

CLS

A6

 

RWD

450/Auto

24 city/31 hwy

n/a

 

AWD

450/Auto

23 city/30 hwy

20 city/29 hwy

3.0T/Auto

Regenerative brakes improve the CLS’ fuel efficiency by converting inertia back into energy instead of wasting it. The A6 doesn’t offer a regenerative braking system.

The CLS has 1.3 gallons more fuel capacity than the A6 (21.1 vs. 19.8 gallons), for longer range between fill-ups.

Transmission

A nine-speed automatic is available on the Mercedes CLS, for better acceleration and lower engine speed on the highway. Only an eight-speed automatic is available for the A6.

Brakes and Stopping

For better stopping power the CLS’ brake rotors are larger than those on the A6:

 

CLS

A6 2.0T

A6 3.0T

Front Rotors

14.2 inches

13.6 inches

14 inches

Rear Rotors

14.2 inches

13 inches

13 inches

The CLS’ standard front and rear disc brakes are vented to help dissipate heat for shorter stops with less fading. The rear discs standard on the A6 2.0T are solid, not vented.

The CLS stops shorter than the A6:

 

CLS

A6

 

70 to 0 MPH

167 feet

171 feet

Car and Driver

Tires and Wheels

For better traction and acceleration, the CLS has larger rear tires than the A6 (275/35R19 vs. 245/45R18). The CLS 450’s rear tires are larger than the largest rear tires available on the A6 (275/35R19 vs. 255/40R19).

The CLS’ 245/40R19 front and 275/35R19 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 A6’s standard 45 series tires.

For better ride, handling and brake cooling the CLS 450 has standard 19-inch wheels. Smaller 18-inch wheels are standard on the A6.

Changing a flat tire near traffic can be dangerous and inconvenient. The run-flat tires standard on the CLS can be driven up to 50 miles without any air pressure, allowing you to drive to a service station for a repair. The A6 doesn’t offer run-flat tires.

Suspension and Handling

The CLS offers an available driver-adjustable suspension system. It allows the driver to choose between an extra-supple ride, reducing fatigue on long trips, or a sport setting, which allows maximum control for tricky roads. The A6’s suspension doesn’t offer adjustable shock absorbers.

The CLS’ drift compensation steering can automatically compensate for road conditions which would cause the vehicle to drift from side to side, helping the driver to keep the vehicle straight more easily. The A6 doesn’t offer drift compensation steering.

For a smoother ride and more stable handling, the CLS’ wheelbase is 1.1 inches longer than on the A6 (115.7 inches vs. 114.6 inches).

The CLS 450 4MATIC handles at .93 G’s, while the A6 3.0T Premium Plus Quattro pulls only .88 G’s of cornering force in a Car and Driver skidpad test.

Passenger Space

The CLS has .6 inches more front legroom, .3 inches more front shoulder room and .2 inches more rear shoulder room than the A6.

Ergonomics

The CLS has a standard remote vehicle starting system, so the vehicle can be started from inside the driver's house. This allows the driver to comfortably warm up the engine before going out to the vehicle. The climate system will also automatically heat or cool the interior. The A6 doesn’t offer a remote starting system.

If the windows are left open on the CLS the driver can close them all at the outside door handle or from a distance using the remote. On a hot day the driver can lower the windows from a distance using the keyless remote. The driver of the A6 can’t use the remote to operate the windows.

The CLS offers an optional 115-volt a/c outlet on the center console, allowing you to recharge a laptop or run small household appliances without special adapters that can break or get misplaced. The A6 doesn’t offer a house-current electrical outlet.

The CLS’ 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 A6 doesn’t offer an automated parking system.

© 1991-2018 Advanta-STAR Automotive Research. All rights reserved.

How much is your car worth?

Get the best value for your car from an Asbury dealership.

Featured Videos