Some tire pressure tables show only the rim
diameters instead of the full tire size, e.g. R18 .
The rim diameter is part of the tire size and can
be found on the tire sidewall ( Y
page 366).
If the tire pressures have been set to the lower
values for lighter loads and/or lower road
speeds, the pressures should be reset to the
higher values: R
if you want to drive with an increased load
and/or R
if you want to drive at higher road speeds
The tire pressures for increased loads and/or
higher road speeds, shown in the tire pressure
table, may have a negative effect on driving
comfort.
If the tire pressure is not set correctly, this can
lead to an excessive build up of heat and a sud-
den loss of pressure.
For more information, contact a qualified spe-
cialist workshop.
Important notes on tire pressure
G WARNING
If the tire pressure drops repeatedly, the
wheel, valve or tire may be damaged. Tire
pressure that is too low may result in a tire
blow-out. There is a risk of an accident. R
Check the tire for foreign objects. R
Check whether the wheel is losing air or the
valve is leaking.
If you are unable to rectify the damage, con-
tact a qualified specialist workshop.
G WARNING
If you fit unsuitable accessories onto tire
valves, the tire valves may be overloaded and
malfunction, which can cause tire pressure
loss. Due to their design, retrofitted tire pres-
sure monitors keep the tire valve open. This
can also result in tire pressure loss. There is a
risk of an accident.
Only screw the standard valve cap or other
valve caps approved by Mercedes-Benz for
your vehicle onto the tire valve.
Use a suitable pressure gauge to check the tire
pressure. The outer appearance of a tire does not permit any reliable conclusion about the tire
pressure. On vehicles equipped with the elec-
tronic tire pressure monitor, the tire pressure
can be checked in the on-board computer.
The tire temperature and pressure increase
when the vehicle is in motion. This is dependent
on the driving speed and the load.
Therefore, you should only correct tire pres-
sures when the tires are cold.
The tires are cold: R
if the vehicle has been parked with the tires
out of direct sunlight for at least three hours
and R
if the vehicle has not been driven further than
1 mile (1.6 km)
The tire temperature changes depending on the
outside temperature, the vehicle speed and the
tire load. If the tire temperature changes by
18 ‡ (10 †), the tire pressure changes by
approximately 10 kPa (0.1 bar/1.5 psi) . Take
thi s into account when checking the pressure of
warm tires. Only correct the tire pressure if it is
too low for the current operating conditions. If
you check the tire pressure when the tires are
warm, the resulting value will be higher than if
the tires were cold. This is normal. Do not
reduce the tire pressure to the value specified
for cold tires. The tire pressure would otherwise
be too low.
Observe the recommended tire pressures for
cold tires: R
on the Tire and Loading Information placard
on the B-pillar on the driver's side R
in the tire pressure table in the fuel filler flap
( Y
page 152) R
printed in yellow on the rim of the emer-
gency/collapsible spare wheel (depending on
vehicle equipment)
Underinflated or overinflated tires
Underinflated tires
G WARNING
Tires with pressure that is too low can over-
heat and burst as a consequence. In addition,
they also suffer from excessive and/or irreg-
ular wear, which can severely impair the brak-
ing properties and the driving characteristics.
There is a risk of an accident.356
Tire pressure
Wheels and tires
