Checking brake fluid levelXPerform a visual check of the brake fluid
reservoir 0046.
The brake fluid level is correct when it
is between the minimum mark and the
maximum mark.
R If the brake fluid level has fallen
slightly below the minimum mark,
drive to an authorized smart center.
R If the brake fluid level has fallen
significantly below the minimum
mark, call Roadside Assistance or an
authorized smart center.XRemount the service flap and close it
( Y page 110).
Tires and wheels
Safety notes
Contact an authorized smart center for
information on tested and recommended
rims and tires for summer and winter
operation. They can also offer advice
concerning tire service and purchase.
GWarning!
Replace rims or tires with the same
designation, manufacturer and type as
shown on the original part. For further
information contact an authorized smart
center. If incorrectly sized rims and tires
are mounted, the wheel brakes or
suspension components can be damaged.
Also, the operating clearance of the wheels
and the tires may no longer be correct.
GWarning!
Worn, old tires can cause accidents. If the
tire tread is worn to minimum tread depth,
or if the tires have sustained damage,
replace them.
When replacing rims, only use genuine
smart wheel bolts specified for the
particular rim type. Failure to do so can
result in the bolts loosening and possibly
an accident.
Retreaded tires are not tested or
recommended by smart, since previous
damage cannot always be recognized on
retreads. The operating safety of the
vehicle cannot be assured when such tires
are used.GWarning!
If you feel a sudden significant vibration
or ride disturbance, or you suspect that
possible damage to your vehicle has
occurred, you should turn on the hazard
warning flashers, carefully slow down, and
drive with caution to an area which is a safe
distance from the road.
Inspect the tires and the vehicle underbody
for possible damage. If the vehicle or tires
appear unsafe, have the vehicle towed to the
nearest authorized smart center or tire
dealer for repairs.
GWarning!
Do not drive with a flat tire. A flat tire
affects the ability to steer or brake the
vehicle. You could 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.
Modifications to the brake system and
wheels and the use of brake dust rings are
not permissible.
Important guidelines
R Only use sets of tires and rims of the same
type and make.
R Tires must be of the correct size for the
rim.
R Break in new tires for approximately
60 miles (100 km) at moderate speeds.
R Regularly check the tires and rims for
damage. Dented or bent rims can cause
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For example, a tire graded 150 would wear
one and one-half (1 1
/ 2) times as well on the
government course as a tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly from
the norm due to variations in driving
habits, service practices and differences
in road characteristics and climate.
Traction GWarning!
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
The traction grades, from highest to
lowest, are AA, A, B, and C. Those grades
represent the tire’s ability to stop on wet
pavement as measured under controlled
conditions on specified government test
surfaces of asphalt and concrete. A tire
marked C may have poor traction
performance.
Temperature
GWarning!
The temperature grade for this tire is
established for a tire that is properly
inflated and not overloaded. Excessive
speed, underinflation, or excessive
loading, either separately or in
combination, can cause excessive heat
build-up and possible tire failure.
The temperature grades are A (the highest),
B, and C, representing the tire’s resistance
to the generation of heat and its ability to
dissipate heat when tested under
controlled conditions on a specified
indoor laboratory test wheel. Sustained
high temperature can cause the material of
the tire to degenerate and reduce tire life,
and excessive temperature can lead to
sudden tire failure. The grade C
corresponds to a level of performance
which all passenger car tires must meet
under the Federal Motor Vehicle Safety
Standard No. 109. Grades B and A represent
higher levels of performance on the
laboratory test wheel than the minimum
required by law.
Rotating tires
GWarning!
Do not rotate front and rear wheels as they
have different dimensions, e.g. rim size,
wheel offset etc. Otherwise, the handling
can be affected and you could endanger
yourself and others.
Thoroughly clean the mounting face of the
wheels and brake discs, i.e. the inner side
of the wheels/tires each time the wheels/
tires are changed. Check for and ensure
proper tire inflation pressure.
GWarning!
Have the tightening torque checked after
changing a wheel. Wheels could become
loose if not tightened with a torque of
81 lb‑ft (110 Nm).
Only use genuine smart wheel bolts
specified for your vehicle’s rims.
For information on wheel change, see “Flat
tire” ( Y page 172).
Tire labeling
Besides tire name (sales designation) and
manufacturer name, a number of markings
can be found on a tire.
Following are some explanations for the
markings on your vehicle’s tires:
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adversely affect handling and fuel
economy, and are more likely to fail from
being overheated.
Do not overinflate tires. Overinflated
tires can adversely affect handling and
ride comfort, wear unevenly, increase
stopping distance, and result in sudden
deflation (blowout) because they are more
likely to become punctured or damaged by
road debris, potholes etc.
Do not overload the tires by exceeding the
specified load limit as indicated on the
Tire and Loading Information placard on
the driver’s door B‑pillar. Overloading the
tires can overheat them, possibly causing
a blowout. Overloading the tires can also
result in handling or steering problems, or
brake failure.XDrive to the nearest authorized smart
center, to have the damaged tire
replaced.XContact an authorized smart center as
soon as possible to obtain a new filler
hose and a new tire sealant container.XBring used tire sealant materials to an
authorized smart center for proper
disposal.XReplace your tire sealant container
every 4 years. Replacement containers
are available at any authorized smart
center.GWarning!
After changing a tire, contact a smart
center to make sure the bolts holding the
wheel to the car are tight enough.
Otherwise, the wheels could come off. Each
bolt should be tightened to a torque of
81 lb‑ft (110 Nm).
Wheel change
Preparing the vehicle
XPark the vehicle on a hard, flat surface
when possible.XTurn on the hazard warning flasher.XTurn the steering wheel so that the front
wheels are in a straight-ahead position.XEngage the parking brake.XMove the gear selector lever to park
position P.XTurn off the engine.XHave any passenger exit the vehicle at a
safe distance from the roadway.
Removing the wheel
GWarning!
When jacking up the vehicle, only use a
suitable jack. Observe the manufacturer’s
safety instructions.
The jack must be designed for jacking up
this vehicle at the jack take-up brackets
built into both sides of the vehicle.
The jack is intended only for lifting the
vehicle briefly for wheel changes. It is not
suited for performing maintenance work
under the vehicle. To help avoid personal
injury, use the jack only to lift the vehicle
during a wheel change.
Never get beneath the vehicle while it is
supported by the jack. Keep hands and feet
away from the area under the lifted vehicle.
Always lower the vehicle onto sufficient
capacity jackstands before working under
the vehicle.
Always firmly engage the parking brake and
block the wheels with wheel chocks or other
sizeable objects before raising the
vehicle with the jack. Do not release the
parking brake while the vehicle is raised.
Make sure the ground on which the vehicle
is standing and where you place the jack is
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solid, level and not slippery. If necessary,
use a large underlay. On slippery surfaces,
such as tiled floors, you should use a non-
slip underlay, for example a rubber mat.
Do not use wooden blocks or similar objects
to support the jack. Otherwise the jack may
not be able to achieve its load-bearing
capacity if it is not at its full height.
The jack must always be vertical when in
use. Always try to use the jack on level
surface. If you do not position the jack
correctly, the vehicle can fall off the jack
and seriously or fatally injure you or
others.
Never start the engine when the vehicle is
raised.
Also observe the notes on the jack.XMake sure to have a suitable jack 17
, wheel
wrench 17
and wheel chock 17
.
Contact an authorized smart center for
information on which jack and wheel
wrench are required.XPrepare the vehicle as described
( Y page 177).XMake sure the surface is level.
Prevent the vehicle from rolling away by
blocking wheels with wheel chocks or other
sizeable objects:
XPlace one wheel chock or other sizeable
object in front of and another wheel
chock or other sizeable object behind
the wheel that is diagonally opposite to
the wheel being changed.
Steel rim with wheel cover
XVehicles with wheel cover on steel rim:
Pull the wheel cover off of the rim.
If necessary, use a suitable tool to pry
the wheel cover off.XOn wheel to be changed, loosen but do not
yet remove the wheel bolts
(approximately one full turn with wheel
wrench).
Steel rim with wheel trim cap
XVehicles with wheel trim cap on steel
rim: On wheel to be changed, loosen but
do not yet remove the wheel bolts
(approximately one full turn with wheel
wrench).XTake the wheel trim cap off.17 Not included and not available as factory equipment.178Wheel change>> Practical hints.
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XPosition jack 0046 under take-up
bracket 0047 so that it is always vertical
as seen from the side, even if the vehicle
is parked on an incline.
The take-up brackets are identified by
the embossed recesses in the area of the
door sills.
! Only position the jack on the
designated take-up brackets. Otherwise,
the vehicle could be damaged.
XJack up the vehicle until the wheel is a
maximum of 1.2 in (3 cm) from the ground.XUnscrew and remove the wheel bolts.
! Do not place wheel bolts in sand or dirt.
This could result in damage to the wheel
bolts and wheel hub threads.
XRemove the wheel.
Mounting the wheel
GWarning!
Always replace wheel bolts that are
damaged or rusted.
Never apply oil or grease to wheel bolts.
Damaged wheel hub threads should be
repaired immediately. Do not continue to
drive under these circumstances! Contact
an authorized smart Center or call
Roadside Assistance.
Incorrect wheel bolts or improperly
tightened wheel bolts can cause the wheel
to come off. This could cause an accident.
Be sure to use the correct wheel bolts.GWarning!
Only use genuine smart wheel bolts. Other
wheel bolts may come loose.
Do not tighten the wheel bolts when the
vehicle is raised. Otherwise the vehicle
could fall off the jack.
XClean contact surfaces of wheel and wheel
hub.
! To avoid paint damage, place wheel flat
against hub and hold it there while
installing first wheel bolt.
XGuide the wheel onto the wheel hub and
push it on.XInsert two wheel bolts and tighten them
slightly.XVehicles with wheel trim cap on steel
rim: Attach the wheel trim cap so that it
is held by the two wheel bolts.XInstall last wheel bolt and tighten it
slightly.XLower the vehicle until the vehicle is
resting fully on its own weight.XRemove the jack.XTighten the wheel bolts. Observe a
tightening torque of 80 lb-ft (110 Nm).GWarning!
Have the tightening torque checked after
changing a wheel. The wheels could come
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