2019 Mercedes S-Class vs. 2019 Cadillac CT6

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


For enhanced safety, the front and rear seat shoulder belts of the Mercedes S-Class have pretensioners to tighten the seatbelts and eliminate dangerous slack in the event of a collision and force limiters to limit the pressure the belts will exert on the passengers. The Cadillac CT6 doesn’t offer pretensioners for the rear seat belts.

The rear seatbelts optional on the S-Class inflate when a collision is detected, helping to spread crash forces over a much larger area of the body and limiting head and neck movement. This can help prevent spinal and internal injuries. The CT6 doesn’t offer inflatable seatbelts.

The S-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 CT6 doesn’t offer a driver alert monitor.

Both the S-Class and the CT6 have standard driver and passenger frontal airbags, front side-impact airbags, driver knee airbags, side-impact head airbags, height adjustable front shoulder belts, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, daytime running lights, rearview cameras, available all wheel drive, night vision systems, around view monitors and rear cross-path warning.


A reliable vehicle saves its owner time, money and trouble. Nobody wants to be stranded or have to be without a vehicle while it’s being repaired. Consumer Reports rates the S-Class’ reliability 14 points higher than the CT6.

J.D. Power and Associates rated the S-Class third among large premium cars in their 2018 Initial Quality Study. The CT6 isn’t in the top three in its category.

J.D. Power and Associates’ 2018 survey of the owners of three-year-old vehicles provides the long-term dependability statistics that show that Mercedes vehicles are more reliable than Cadillac vehicles. J.D. Power ranks Mercedes 15th in reliability. With 39 more problems per 100 vehicles, Cadillac is ranked 27th.

From surveys of all its subscribers, Consumer Reports’ December 2018 Auto Issue reports that Mercedes vehicles are more reliable than Cadillac vehicles. Consumer Reports ranks Mercedes 11 places higher in reliability than Cadillac.


The S-Class has more powerful engines than the CT6:




S 450 3.0 turbo V6

362 HP

369 lbs.-ft.

S 560 4.0 turbo V8

463 HP

516 lbs.-ft.

AMG S 63 4.0 turbo V8

603 HP

664 lbs.-ft.

AMG S 65/Maybach S 650 6.0 turbo V12

621 HP

738 lbs.-ft.

CT6 2.0 turbo 4 cyl.

265 HP

295 lbs.-ft.

CT6 3.6 DOHC V6

335 HP

285 lbs.-ft.

CT6 3.0 turbo V6

404 HP

400 lbs.-ft.

CT6 V-Sport 4.2 turbo V8

550 HP

627 lbs.-ft.

As tested in Motor Trend the S 560 is faster than the Cadillac CT6 twin turbo V6:




Zero to 60 MPH

4.7 sec

5.1 sec

Quarter Mile

13.2 sec

13.6 sec

Speed in 1/4 Mile

107.7 MPH

102.3 MPH

Fuel Economy and Range

On the EPA test cycle the S 450 4MATIC gets better fuel mileage than the CT6 AWD V6 (18 city/28 hwy vs. 18 city/27 hwy). The S 450 4MATIC gets better fuel mileage than the CT6 AWD turbo V6 (18 city/28 hwy vs. 18 city/26 hwy).

Regenerative brakes improve the S-Class Hybrid’s fuel efficiency by converting inertia back into energy instead of wasting it. The CT6 doesn’t offer a regenerative braking system.

The S-Class’ standard fuel tank has 1.6 gallons more fuel capacity than the CT6 (21.1 vs. 19.5 gallons), for longer range between fill-ups. The S-Class V12’s standard fuel tank has 5.1 gallons more fuel capacity than the CT6 (24.6 vs. 19.5 gallons).

Brakes and Stopping

For better stopping power the S-Class’ brake rotors are larger than those on the CT6:


S 450/560

S 63/65

CT6 2.0


Front Rotors

14.6 inches

16.5 inches

12.6 inches

13.6 inches

Rear Rotors

14.2 inches

14.2 inches

12.4 inches

12.4 inches

The S-Class S 63/65 offers optional heat-treated ceramic brake rotors, which last ten to twenty times as long as conventional cast iron rotors, don’t rust, don’t fade during repeated high speed braking, and their lighter weight contribute to better braking, handling and acceleration. The CT6 doesn’t offer ceramic brake rotors.

The S-Class stops shorter than the CT6:





60 to 0 MPH

114 feet

117 feet

Motor Trend

Tires and Wheels

For better traction, the S-Class has larger standard tires than the CT6 (245/50R18 vs. 235/50R18). The S 63’s tires are larger than the largest tires available on the CT6 (F:255/40R20 & R:285/35R20 vs. 245/45R19).

The S 63’s 285/35R20 rear tires provide better handling because they have a lower 35 series profile (height to width ratio) that provides a stiffer sidewall than the CT6’s optional 40 series tires.

Changing a flat tire near traffic can be dangerous and inconvenient. The run-flat tires available on the S-Class can be driven up to 50 miles without any air pressure, allowing you to drive to a service station for a repair. The CT6 doesn’t offer run-flat tires.

Suspension and Handling

The front and rear suspension of the S-Class uses air springs for a smoother, controlled ride than the CT6, which uses coil springs. Air springs maintain proper ride height and ride more smoothly.

The S-Class offers an available adjustable active suspension system, which counteracts cornering forces actively, limiting body roll and improving handling and stability. Cadillac doesn’t offer an active suspension on the CT6.

The S-Class has a standard automatic front and rear load leveling suspension to keep ride height level with a heavy load or when towing. The CT6 doesn’t offer a load leveling suspension.

For a smoother ride and more stable handling, the S-Class’ wheelbase is 2.2 inches longer than on the CT6 (124.6 inches vs. 122.4 inches). The Maybach S-Class’ wheelbase is 10.1 inches longer than on the CT6 (132.5 inches vs. 122.4 inches).

The S 600 handles at .90 G’s, while the CT6 pulls only .82 G’s of cornering force in a Motor Trend skidpad test.

The S 600 executes Motor Trend’s “Figure Eight” maneuver quicker than the CT6 (25.8 seconds @ .75 average G’s vs. 26.7 seconds @ .66 average G’s).

For better maneuverability, the S AMG S 65’s turning circle is 1.9 feet tighter than the CT6’s (38.1 feet vs. 40 feet).


As tested by Car and Driver, the interior of the S 560 is quieter than the CT6 AWD:




At idle

40 dB

49 dB

Passenger Space

The S-Class has 1.4 inches more front shoulder room and 2.9 inches more rear shoulder room than the CT6.

Cargo Capacity

The S-Class has a larger trunk than the CT6 (16.3 vs. 15.8 cubic feet).

A low lift-over trunk design makes loading and unloading the S-Class easier. The S-Class’ trunk lift-over height is 27.4 inches, while the CT6’s liftover is 29.1 inches.

A standard locking glovebox keeps your small valuables safer in the S-Class. The CT6 doesn’t offer locking storage for small valuables.


Heated windshield washer fluid is standard on the S-Class to defrost the washer nozzles and quickly clear ice and frost from the windshield without scraping. The CT6 doesn’t offer heated windshield washer fluid.

The CT6 Premium Luxury/Platinum/Sport’s cornering lamps activate a lamp on the front corner when the turn signal is activated. The S-Class’ 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 better shield the driver and front passenger’s vision, the S-Class has standard dual-element sun visors that can block glare from two directions simultaneously. The CT6 doesn’t offer secondary sun visors.

Model Availability

The Mercedes S-Class comes in coupe, convertible and sedan bodystyles; the Cadillac CT6 isn’t available as a coupe or convertible.

Economic Advantages

Insurance will cost less for the S-Class owner. The Car Book by Jack Gillis rates the S-Class with a number “1” insurance rate while the CT6 is rated higher at a number “3” rate.

According to The Car Book by Jack Gillis, the S-Class is less expensive to operate than the CT6 because it costs $162 less to do the manufacturer’s suggested maintenance for 50,000 miles. Typical repairs cost much less on the S-Class than the CT6, including $89 less for front brake pads, $124 less for fuel injection, $45 less for a fuel pump and $259 less for a timing belt/chain.


Consumer Reports® recommends the Mercedes S-Class, based on reliability, safety and performance.

The Mercedes S-Class outsold the Cadillac CT6 by 61% during the 2018 model year.

© 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