Certified Benz & Beemer Compares 2015 Audi A8 VS 2015 Mercedes S-Class Near Scottsdale, AZ

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2015 Audi A8

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2015 Mercedes S-Class

Safety Comparison

Both the A8 and S-Class have child safety locks to prevent children from opening the rear doors. The A8 has power child safety locks, allowing the driver to activate and deactivate them from the driver's seat and to know when they're engaged. The S-Class’ child locks have to be individually engaged at each rear door with a manual switch. The driver can’t know the status of the locks without opening the doors and checking them.

The A8 has standard Secondary Collision Brake Assist, which automatically apply the brakes in the event of a crash to help prevent secondary collisions and prevent further injuries. The S-Class doesn’t offer a post collision braking system: in the event of a collision that triggers the airbags, more collisions are possible without the protection of airbags that may have already deployed.

To provide maximum traction and stability on all roads, All-Wheel Drive is standard on the A8. But it costs extra on the S-Class.

Both the A8 and the S-Class have standard driver and passenger frontal airbags, front and rear side-impact airbags, driver knee airbags, side-impact head airbags, front seatbelt pretensioners, height adjustable front shoulder belts, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, daytime running lights, rearview cameras, available crash mitigating brakes, night vision systems, lane departure warning systems, blind spot warning systems, around view monitors and rear cross-path warning.

Warranty Comparison

The A8’s corrosion warranty is 8 years and unlimited miles longer than the S-Class’ (12/unlimited vs. 4/50,000).

Reliability Comparison

J.D. Power and Associates’ 2014 Initial Quality Study of new car owners surveyed provide the statistics that show that Audi vehicles are better in initial quality than Mercedes vehicles. J.D. Power ranks Audi 11th in initial quality, above the industry average. With 4 more problems per 100 vehicles, Mercedes is ranked 13th.

Engine Comparison

As tested in Car and Driver the A8 4.0T is faster than the S600:



Zero to 60 MPH

3.9 sec

4.7 sec

Zero to 100 MPH

9.8 sec

10.6 sec

5 to 60 MPH Rolling Start

5 sec

5.1 sec

Quarter Mile

12.4 sec

13.1 sec

Top Speed

131 MPH

130 MPH

Fuel Economy and Range Comparison

On the EPA test cycle the A8 L TDI gets better fuel mileage than the S550 4MATIC (24 city/36 hwy vs. 16 city/26 hwy). The A8 L TDI gets better fuel mileage than the S550 RWD (24 city/36 hwy vs. 17 city/26 hwy).

On the EPA test cycle the A8 gets better fuel mileage than the S-Class:




17 city/26 hwy




19 city/29 hwy



18 city/30 hwy

16 city/26 hwy


On the EPA test cycle the A8 L W12 gets better fuel mileage than the S600 (14 city/22 hwy vs. 13 city/21 hwy). The A8 L W12 gets better fuel mileage than the S65 AMG (14 city/22 hwy vs. 13 city/20 hwy).

An engine control system that can shut down half of the engine’s cylinders helps improve the A8 4.0T/W12’s fuel efficiency. The S-Class doesn’t offer a system that can shut down part of the engine.

Regenerative brakes improve the A8’s fuel efficiency by converting inertia back into energy instead of wasting it. The S-Class doesn’t offer a regenerative braking system.

The A8 has 1.9 gallons more fuel capacity than the S-Class (23.8 vs. 21.9 gallons), for longer range between fill-ups.

Brakes and Stopping Comparison

For better stopping power the A8’s standard front brake rotors are larger than those on the S-Class:



Front Rotors

15 inches

14.6 inches

The A8 stops shorter than the S-Class:



70 to 0 MPH

169 feet

171 feet

Car and Driver

Tires and Wheels Comparison

For better traction, the A8 has larger standard tires than the S-Class (255/45R19 vs. 245/40R20). The A8’s optional tires are larger than the largest tires available on the S-Class (265/40R20 vs. 255/40R20).

For better ride, handling and brake cooling the A8 has standard 19-inch wheels. Smaller 18-inch wheels are standard on the S-Class.

Suspension and Handling Comparison

For better handling and stability, the track (width between the wheels) on the A8 is 1.7 inches wider in the front and 1.2 inches wider in the rear than on the S-Class.

The A8 handles at .95 G’s, while the S550 pulls only .83 G’s of cornering force in a Motor Trend skidpad test.

The A8 executes Motor Trend’s “Figure Eight” maneuver quicker than the S550 (25.7 seconds @ .73 average G’s vs. 26.5 seconds @ .7 average G’s).

Chassis Comparison

The Audi A8 may be more efficient, handle and accelerate better because it weighs about 250 pounds less than the Mercedes S-Class.

The A8 is 4.3 inches shorter than the S-Class, making the A8 easier to handle, maneuver and park in tight spaces.

The A8 3.0T/4.0T/TDI uses computer-generated active noise cancellation to help remove annoying noise and vibration from the passenger compartment, especially at low frequencies. The S-Class doesn’t offer active noise cancellation.

Ergonomics Comparison

The A8 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 S-Class doesn’t offer a remote starting system.

In poor weather, headlights can lose their effectiveness as grime builds up on their lenses. This can reduce visibility without the driver realizing. The A8 has standard headlight washers to keep headlight output high. The S-Class doesn’t offer headlight washers.

Economic Advantages Comparison

Insurance will cost less for the A8 owner. The Complete Car Cost Guide estimates that insurance for the A8 will cost $2115 less than the S-Class over a five-year period.

Intellichoice estimates that five-year ownership costs (depreciation, financing, insurance, fuel, fees, repairs and maintenance) for the Audi A8 will be $16713 to $88672 less than for the Mercedes S-Class.

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