311 Operation
Tires and wheels
Tires and wheels
See an authorized Mercedes-Benz Center
for information on tested and recommend-
ed rims and tires for summer and winter
operation. They can also offer advice con-
cerning tire service and purchase.
Retreaded tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on
retreads. Mercedes-Benz can therefore
not assure the operating safety of the vehi-
cle when such tires are used.
See an authorized Mercedes-Benz Center
for information on tested and recommend-
ed rims and tires for summer and winter
operation.
Important guidelines
Only use sets of tires and rims of the
same type and make.
Tires must be of the correct size for the
rim.
Break in new tires for approximately
60 miles (100 km) at moderate
speeds.
Regularly check the tires and rims for
damage. Dented or bent rims can
cause tire inflation pressure loss and
damage to the tire beads.
If vehicle is heavily loaded, check tire
inflation pressure and correct as re-
quired.
Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths under
1/8in (3 mm).
When replacing individual tires, you
should mount new tires on the front
wheels first (on vehicles with
same-sized wheels all around).
Warning!
G
Replace rims or tires with the same designa-
tion, manufacturer and type as shown on the
original part. See an authorized
Mercedes-Benz Center for further informa-
tion. If incorrectly sized rims and tires are
mounted:
The wheel brakes or suspension compo-
nents can be damaged
The correct operating clearance of the
wheels and the tires are no longer guar-
anteed
Warning!
G
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
When replacing rims, only use genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can re-
sult in the bolts loosening and possibly an
accident.
323 Operation
Tires and wheels
Switch on the ignition (
page 33).
Press buttonè orÿ on the mul-
tifunction steering wheel repeatedly
until the standard display menu ap-
pears in the multifunction display
(page 150).
Press the j or k button until the
current inflation pressures for each tire
appear in the multifunction display.iPossible differences between the read-
ings of a tire inflation pressure gauge of
an air hose, e.g. gas station equipment,
and the vehicle’s control system can
occur. The readings issued by the con-
trol system are more precise.
Warning!
G
When the tire pressure monitoring system
warning light is lit, one or more of your tires
is significantly under-inflated. You should
stop and check your tires as soon as possi-
ble, and inflate them to the proper pressure
as indicated on the vehicle’s tire information
placard. Driving on a significantly under-in-
flated tire causes the tire to overheat and
can lead to tire failure. Under-inflation also
reduces fuel efficiency and tire tread life,
and may affect the vehicle’s handling and
stopping ability. Each tire, including the
spare, should be checked monthly when
cold and set to the recommended inflation
pressure as specified in the vehicle placard
and owner’s manual.iThe recommended tire inflation pres-
sures for your vehicle can be found on
the placard on the driver’s door B-pillar
or the inside of the fuel filler flap, not in
the owner’s manual.
Warning!
G
The tire pressure monitoring system does
not indicate a warning for wrongly selected
inflation pressures. Always adjust tire infla-
tion pressure according to the placard locat-
ed on the driver’s door B-pillar or the inside
of the fuel filler flap.
The tire pressure monitoring system is not
able to issue a warning due to a sudden dra-
matic loss of pressure (e.g. tire blowout
caused by a foreign object). In this case
bring the vehicle to a halt by carefully apply-
ing the brakes and avoiding abrupt steering
maneuvers.iOperating radio transmission equip-
ment (e.g. wireless headsets, two-way
radios) in or near the vehicle could
cause the tire pressure monitoring sys-
tem to malfunction.
337 Operation
Tires and wheels
Tire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power
seats, radio, and heater, to the extent that
these items are available as
factory-installed equipment (whether
installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire.
Air pressure is expressed in pounds per
square inch (psi), or kilopascal (kPa) or
bars.
Aspect ratio
Dimensional relationship between tire
section height and section width
expressed in percentage.Bar
Another metric unit for air pressure. There
are 14.5038 pounds per square inch (psi)
to 1 bar; there are 100 kilopascals (kPa)
to 1 bar.
Bead
The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the
rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle
has been sitting for at least three hours or
driven no more than one mile (1.6 km).
Curb weight
The weight of a motor vehicle with stan-
dard equipment including the maximum
capacity of fuel, oil, and coolant, and, if so
equipped, air conditioning and additional
optional equipment, but without passen-
gers and cargo.DOT (D
epartment o
f T
ransportation)
A tire branding symbol which denotes the
tire meets requirements of the
U.S. Department of Transportation.
GAWR (G
ross A
xle W
eight R
ating)
The GAWR is the maximum permissible
axle weight. The gross vehicle weight on
each axle must never exceed the GAWR for
the front and rear axle indicated on the
certification label located on the driver's
door B-pillar.
GVW (G
ross V
ehicle W
eight)
The GVW comprises the weight of the
vehicle including fuel, tools, spare wheel,
installed accessories, passengers and
cargo and, if applicable, trailer tongue
load. The GWV must never exceed the
GWVR indicated on the certification label
located on the driver's door B-pillar.
338 OperationTires and wheelsGVWR (G
ross V
ehicle W
eight R
ating)
This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight of
the vehicle including all options, passen-
gers, fuel, and cargo and, if applicable,
trailer tongue load). It is indicated on
certification label located on the driver's
door B-pillar.
Kilopascal (kPa)
The metric unit for air pressure. There are
6.9 kPa to one psi; another metric unit for
air pressure is bars. There are
100 kilopascals (kPa) to one bar.
Maximum load rating
The maximum load in kilograms and
pounds that can be carried by the tire.
Maximum loaded vehicle weight
The sum of curb weight, accessory weight,
vehicle capacity weight and production
options weight.Maximum tire inflation pressure
This number is the greatest amount of air
pressure that should ever be put in the tire
under normal driving conditions.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by
68 kilograms (150 lbs).
Occupant distribution
The distribution of occupants in a vehicle
at their designated seating positions.
Production options weight
The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, roof rack, heavy duty
battery, and special trim.PSI (P
ounds per s
quare i
nch)
A standard unit of measure for air pressure
-> bar, kilopascal (kPa).
Recommended tire inflation pressure
Recommended tire inflation pressure
listed on placard located on driver's door
B-pillar for normal driving conditions.
Provides best handling, tread life and
riding comfort.
Rim
A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated.
Sidewall
The portion of a tire between the tread and
the bead.
361 Practical hints
What to do if …
Problem
Possible cause
Suggested solution
D
The red coolant warning lamp
comes on when the engine is
running.
There is insufficient coolant in the reservoir.
If this warning lamp comes on frequently,
there is a leak in the cooling system.
If the coolant level is correct, the electric ra-
diator fan may be broken.
Immediately add coolant to prevent
engine from overheating
(page 308).
Have the cooling system checked.
If the coolant temperature is below
257°F (125°C), you can continue
driving to the nearest authorized
Mercedes-Benz Center.
Avoid high engine loads (e.g. driving
uphill) and stop-and-go driving.
D
The red coolant warning lamp
comes on while driving and you
hear a warning sound.
The coolant temperature has exceeded
257°F (125°C).
Stop as soon as possible and allow
the engine and coolant to cool down.
l
The red DTR warning lamp
comes on while driving.
You are too close to the vehicle in front of you
to maintain selected speed.
Apply the brakes immediately to in-
crease the following distance.
Warning!
G
Driving when your engine is badly overheat-
ed can cause some fluids which may have
leaked into the engine compartment to
catch fire. You could be seriously burned.
Steam from an overheated engine can cause
serious burns and can occur just by opening
the engine hood. Stay away from the engine
if you see or hear steam coming from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until the
engine has cooled down.
362 Practical hintsWhat to do if …Problem
Possible cause
Suggested solution
l
The red DTR warning lamp
comes on while driving and you
hear a warning chime sound.
You are gaining too rapidly on the vehicle
ahead of you.
The distance warning system has recog-
nized a stationary obstacle on your prob-
able line of travel.
Apply the brakes immediately.
Carefully observe the traffic situation.
You may need to brake or maneuver
to avoid hitting an obstacle.
W
The yellow fuel tank reserve
warning lamp comes on while
driving.
The fuel level has gone below the reserve
mark.
Refuel at the next gas station
(page 299).
<
The red seat belt telltale comes
on after starting the engine with
all doors closed.
The seat belt telltale reminds you and your
front passenger to fasten your seat belts be-
fore driving off.
Fasten your seat belts.
The red seat belt telltale flashes
and you additionally hear an in-
termittent warning signal with in-
creasing intensity for a maximum
of 60 seconds when the vehicle’s
speed exceeds 15 mph
(25 km/h).
You and/or your front passenger have for-
gotten to fasten your seat belts.
There are items placed on the front passen-
ger seat and therefore the system senses the
front passenger seat as being occupied.
Fasten your seat belts.
Remove the items from the front pas-
senger seat and put them in a safe
place.
381 Practical hints
What to do if …
Display symbol
Display messages
Possible cause
Possible solution
(USA only);(Canada only)3
Reduced braking power
Visit workshop
The SBC brake system is in emergency
operation mode. Considerable brake ped-
al force is required and the stopping dis-
tance is increased.
Continue driving with added caution.
Adjust driving to be consistent with
reduced braking responsiveness.
Visit an authorized Mercedes-Benz
Center as soon as possible.
Service brake
Visit workshop
There are malfunctions, but the SBC
brake system is operating normally.
Visit an authorized Mercedes-Benz
Center as soon as possible.
Brake overheated
Drive carefully
The brake system is overheated due to an
excessive load on the brakes.
Relieve the load on the brake system.
Drive more smoothly and think ahead
to avoid unnecessary braking.
When driving down slopes, shift into a
lower gear to use the engine’s braking
power (
page 176).
Cautiously continue driving so that
the air stream will cool down the
brakes.
Release
parking brake
You are driving with the parking brake
set.
Release the parking brake
(page 48).
382 Practical hintsWhat to do if …Display symbol
Display messages
Possible cause
Possible solution
(USA only);(Canada only)3
Brake fluid
Visit workshop
There is insufficient brake fluid in the
reservoir.
Risk of accident! Stop the vehicle and
notify an authorized Mercedes-Benz
Center. Do not add brake fluid! This
will not solve the problem.
Warning!
G
Driving while these messages are displayed
can result in an accident. Have your brake
system checked immediately.
If there is a malfunction in the SBC brake
system, we recommend that the vehicle be
transported with all wheels off the ground
using flatbed or appropriate wheel lift/dolly
equipment.
A tow bar must be used if circumstances do
not permit the use of the recommended
towing methods and the vehicle requires
towing with all four wheels on the ground.
Towing the vehicle with all four wheels on
the ground is only permissible for distances
u p t o 3 0 m i l e s ( 5 0 k m ) a n d a t a s p e e d n o t t o
exceed 30 mph (50 km / h). For more infor-
mation, refer to “Towing the vehicle”
(page 439).
If the SBC brake system enters its emergen-
cy operation mode, the driver must apply
significantly greater brake pedal pressure
and depress the pedal much further than
normal to obtain braking effect. If neces-
sary, apply full pressure to the brake pedal.
Brakes may only be applied to the front
wheels. Stopping distance is increased!
Do not add brake fluid before checking the
brake system. Overfilling the brake fluid res-
ervoir can result in spilling brake fluid on hot
engine parts and the brake fluid catching
fire. You can be seriously burned.!If you find that the brake fluid in the
brake fluid reservoir has fallen to the
minimum mark or below, have the
brake system checked for brake pad
thickness and leaks.!Brake pad thickness must be visually
inspected by a qualified technician at
the intervals specified in the
Maintenance Booklet.