Mercedes Benz 2009 M-Class User Manual

Treadwear indicators (TWI) are required by 
law. These indicators are located in six 
places on the tread circumference and 
become visible at a tread depth of 
approximately 

1

/

16

in (1.6 mm), at which 

point the tire is considered worn and 
should be replaced.

The treadwear indicator appears as a solid 
band across the tread.

Specified tire inflation pressures must be 
maintained. This applies particularly if the 
tires are subjected to high loads (e.g. high 
speeds, heavy loads, high ambient temper-
atures).

For more information, see “Tires and 
wheels” (

컄

page 365).

Depending on the depth of the water layer 
on the road, hydroplaning may occur, even 
at low speeds and with new tires. Reduce 
vehicle speed, avoid track grooves in the 
road and apply brakes cautiously in the 
rain.

The safe speed on a wet, snow covered or 
icy road is always lower than on a dry road.

You should pay particular attention to the 
condition of the road whenever the outside 
temperatures are close to the freezing 
point.

G

Although the applicable federal motor 

vehicle safety laws consider a tire to be 

worn when the treadwear indicators (TWI) 

become visible at approximately 

1

/

16

in 

(1.6 mm), we recommend that you do not 

allow your tires to wear down to that level. 

As tread depth approaches 

1

/

8

in (3 mm), 

the adhesion properties on a wet road are 

sharply reduced.

Depending upon the weather and/or road 

surface (conditions), the tire traction varies 

widely.

G

Do not drive with a flat tire. A flat tire affects 

the ability to steer or brake the vehicle. You 

may lose control of the vehicle. Continued 

driving with a flat tire or driving at high 

speed with a flat tire will cause excessive 

heat build-up and possibly a fire.

G

If ice has formed on the road, tire traction 

will be substantially reduced. Under such 

weather conditions, drive, steer and brake 

with extreme caution.