280 Operation
Driving instructions
Power assistanceBrakes
To help prevent brake disc corrosion after 
driving on wet road surfaces (particularly 
salted roads), it is advisable to brake the 
vehicle with considerable force prior to 
parking. The heat generated serves to dry 
the brakes.
If your brake system is normally only sub-
jected to moderate loads, you should occa-
sionally test the effectiveness of the 
brakes by applying above-normal braking 
pressure at higher speeds. This will also 
enhance the grip of the brake pads.
Warning!G
With the engine not running, there is no 
power assistance for the brake and steering 
systems. In this case, it is important to keep 
in mind that a considerably higher degree of 
effort is necessary to brake and steer the 
vehicle.
Warning!G
After driving in heavy rain for some time 
without applying the brakes or through wa-
ter deep enough to wet brake components 
or salty road conditions, the first braking ac-
tion may be somewhat reduced and in-
creased pedal pressure may be necessary to 
obtain expected braking effect. Maintain a 
safe distance from vehicles in front.
Resting your foot on the brake pedal will 
cause excessive and premature wear of the 
brake pads.
It can also result in the brakes overheating, 
thereby significantly reducing their effec-
tiveness. It may not be possible to stop the 
vehicle in sufficient time to avoid an acci-
dent.
!Because the ESP® operates automatically, 
the engine must be turned off (SmartKey in 
starter switch position0 or1) when
the parking brake is being tested on a brake 
test dynamometer
the vehicle is being towed with the front axle 
raised
Active braking action through the ESP
® may 
otherwise seriously damage the brake system. 
281 Operation
Driving instructions
Refer to the description of the Brake Assist 
System (BAS) (
page 86).
Brake pad wear or a leak in the system may 
be the reason for low brake fluid in the res-
ervoir.
The brake fluid level in the reservoir may 
be too low if the brake warning lamp in 
the instrument cluster (
page 26) 
comes on although the parking brake is 
released (
page 350). Observe additional 
messages that may appear in the multi-
function display (
page 373).
Have the brake system inspected immedi-
ately. Contact an authorized 
Mercedes-Benz Center.All checks and service work on the brake 
system should be carried out by qualified 
technicians only. Contact an authorized 
Mercedes-Benz Center.
Install only brake pads and brake fluid 
recommended by Mercedes-Benz.
After hard braking, it is advisable to drive 
on for some time, rather than immediately 
park, so that the air stream will cool down 
the brakes faster.High-performance brake system 
(SLK 55 AMG only)
The high-performance brake system is de-
signed to operate under the extremely high 
operating demands required to accommo-
date the performance capabilities of the 
vehicle. The brakes may produce a squeak-
ing-type noise depending on the
vehicle speed
brake force applied
ambient conditions, e.g. temperature 
and humidity
As with any brake system, the wear of indi-
vidual brake system components such as 
brake pads or discs strongly depends on 
your driving style and the conditions under 
which you operate the vehicle. Thus, a driv-
ing style calling for high demand braking 
will cause your vehicle’s brakes to wear 
more quickly.
Warning!G
Make sure not to endanger any other road 
users when carrying out these braking 
maneuvers.
Warning!G
If other than recommended brake pads are 
installed, or other than recommended brake 
fluid is used, the braking properties of the 
vehicle can be degraded to an extent that 
safe braking is substantially impaired. This 
could result in an accident.
!When driving down long and steep grades, 
relieve the load on the brakes by shifting into a 
lower gear to use the engine’s braking power. 
This helps prevent overheating of the brakes and 
reduces brake pad wear.