Compare the2025 Mercedes AMG SLVS 2025 BMW M4

For enhanced safety, the front and rear seat shoulder belts of the Mercedes AMG SL 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 BMW M4 doesn’t offer pretensioners for its rear seat belts.

Earlier warning of stopped traffic, traffic signals, dangerous road conditions, weather, or accidents, can keep driver's safer and prevent crashes. The AMG SL has Car-to-X Communication, a system that seamlessly communicates important warnings to the driver about impending danger, if they're available. The M4 doesn’t offer a system that can receive automated systems from infrastructure or other vehicles.

Both the AMG SL and M4 have rear cross-traffic warning, but the AMG SL has Rear Cross Traffic Brake (automatically applies the brakes) to better prevent a collision when backing near traffic. The M4’s Cross Traffic Warning doesn’t automatically brake.

Both the AMG SL and the M4 have standard driver and passenger frontal airbags, front side-impact airbags, driver and front passenger knee airbags, side-impact head airbags, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, crash mitigating brakes, daytime running lights, blind spot warning systems, rearview cameras, rear cross-path warning, driver alert monitors and available lane departure warning systems.

There are over 10 percent more Mercedes dealers than there are BMW dealers, which makes it easier should you ever need service under the AMG SL’s warranty.

The AMG SL has more powerful engines than the M4:

On the EPA test cycle the AMG SL running its gasoline engine gets better mileage than the M4 Convertible:

The AMG SL has 2.9 gallons more fuel capacity than the M4 (18.5 vs. 15.6 gallons), for longer range between fill-ups.

The Mercedes AMG SL comes standard with an automatic transmission, for driver comfort, especially in the city. Automatic costs extra on the M4.

The AMG SL offers a standard sequential manual gearbox (SMG). With no clutch pedal to worry about and a fully automatic mode, an SMG is much more efficient than a conventional automatic but just as easy to drive. The M4 doesn’t offer an SMG.

For better stopping power the AMG SL’s front brake rotors are larger than those on the M4:

For better ride, handling and brake cooling the AMG SL 43 has standard 19-inch wheels. Smaller 18-inch front wheels are standard on the M4. The AMG SL’s optional 21-inch wheels are larger than the 19-inch front wheels and 20-inch rear wheels optional on the M4.

The AMG SL offers an available adjustable active suspension system, which counteracts cornering forces actively, limiting body roll and improving handling and stability. BMW doesn’t offer an active suspension on the M4.

The AMG SL’s 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 M4 doesn’t offer drift compensation steering.

For better handling and stability, the average track (width between the wheels) on the AMG SL is 1.8 inches wider in the front and .8 inches wider in the rear than the track on the M4.

The AMG SL is 3.9 inches shorter than the M4, making the AMG SL easier to handle, maneuver and park in tight spaces.

To almost totally eliminate engine vibration in the passenger area, the AMG SL 63 has an electronically controlled liquid-filled front engine mount and conventional liquid-filled engine mounts (standard liquid front mount on other versions of the AMG SL). A computer-controlled electric current in the liquid changes its viscosity, allowing the mount to dampen the engine completely at all RPMs. The M4 uses conventional solid rubber engine mounts.

The design of the Mercedes AMG SL amounts to more than styling. The AMG SL has an aerodynamic coefficient of drag of .31 Cd. That is lower than the M4 (.34) and many sports cars. A more efficient exterior helps keep the interior quieter and helps the AMG SL get better fuel mileage.

The front grille of the AMG SL uses electronically controlled shutters to close off airflow and reduce drag when less engine cooling is needed. This helps improve highway fuel economy. The M4 doesn’t offer active grille shutters.

Unlike the driver-only memory system in the M4, the AMG SL has standard driver and passenger memory, so that when drivers switch, the memory setting adjusts the driver’s seat, steering wheel position and outside mirror angle and the front passenger seat also adjusts to the new passenger’s preset preferences.

The AMG SL’s standard easy entry and exit feature raises the steering wheel and glides the driver’s seat back, making it easier for the driver to get in and out. The M4 doesn’t offer an easy entry system.

Heated windshield washer fluid is standard on the AMG SL to defrost the washer nozzles and quickly clear ice and frost from the windshield without scraping. The M4 doesn’t offer heated windshield washer fluid.

The AMG SL has a standard heated steering wheel to take the chill out of steering on extremely cold winter days before the car heater warms up. A heated steering wheel costs extra on the M4.

The AMG SL has a standard center folding armrest for the rear passengers. A center armrest helps make rear passengers more comfortable and it can provide a boundary between children. The M4 doesn’t offer a rear seat center armrest.

The AMG SL has standard massaging front seats in order to maximize comfort and eliminate fatigue on long trips. Massaging seats aren’t available in the M4.