wheel bolts MERCEDES-BENZ SLK55AMG 2008 R171 Owner's Manual

Contents
At the gas station .............................. 291
Refueling ...................................... 291
Check regularly and before a
long trip........................................ 292
Engine compartment ......................... 294
Hood ............................................ 294
Engine oil ..................................... 296
Transmission fluid level* .............. 300
Coolant level ................................ 300
Windshield washer system and
headlamp cleaning system* ......... 301
Battery ......................................... 302
Tires and wheels ................................ 304
Important guidelines .................... 304
Tire care and maintenance........... 305
Direction of rotation ..................... 307
Loading the vehicle ...................... 307
Recommended tire inflation
pressure ....................................... 311
Checking tire inflation pressure ... 313
MOExtended system* .................. 321
Tire labeling.................................. 321
Load identification ....................... 325
DOT, Tire Identification
Number (TIN) ............................... 326
Maximum tire load ....................... 327Maximum tire inflation pressure ... 328
Uniform Tire Quality Grading
Standards (U.S. vehicles) .............. 328
Tire ply material ............................ 330
Tire and loading terminology......... 331
Rotating tires ................................ 334
Winter driving ..................................... 335
Winter tires ................................... 335
Snow chains.................................. 336
Maintenance....................................... 337
Maintenance service indicator
message ....................................... 337
Clearing the maintenance
service indicator message ............ 338
Maintenance service term
exceeded ...................................... 338
Calling up the maintenance
service indicator display ............... 338
Resetting the maintenance
service indicator ........................... 339
Vehicle care........................................ 340
Cleaning and care of vehicle ......... 340
Practical hints.................................. 347
What to do if … ................................... 348
Lamps in instrument cluster ......... 348
Lamp in center console ................ 358
Vehicle status messages in the
multifunction display .................... 360
Where will I find...? ............................. 389
First aid kit.................................... 389
Vehicle tool kit, vehicle jack ......... 389
Spare wheel with collapsible tire .. 392
Spare wheel bolts ......................... 393
Unlocking/locking in an emergency .. 394
Unlocking the vehicle ................... 394
Locking the vehicle ....................... 395
Manually unlocking the gear
selector lever
(automatic transmission*) ............ 396
Opening/closing in an emergency ..... 397
Raising retractable hardtop
manually ....................................... 397
Replacing SmartKey batteries ............ 398
Replacing bulbs .................................. 400
Bulbs............................................. 400
Replacing bulbs for front lamps .... 403
Replacing bulbs for rear lamps ..... 404

304 Operation
Tires and wheels
Contact an authorized Mercedes-Benz
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.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 or
damage the tire beads.

If vehicle is heavily loaded, check tire
inflation pressure and correct as
required.

Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths of less than
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. Contact 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 operating clearance of the wheels
and the tires may no longer be correct.
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 may lead to
an accident.
Retreaded tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on
retreads. Mercedes-Benz therefore cannot
assure the operating safety of the vehicle
when such tires are used.

334 Operation
Tires and wheels
Rotating tires
Tire rotation can be performed on vehicles
with tires of the same dimension all
around. If your vehicle is equipped with
tires of the same dimension all around,
tires can be rotated, observing a
front-to-rear rotation pattern that will
maintain the intended rotation (spinning)
direction of the tire (
page 307).
In some cases, such as when your vehicle
is equipped with mixed-size tires (different
tire dimension front vs. rear), tire rotation
is not possible.If applicable to your vehicle’s tire configu-
ration, tires can be rotated according to
the tire manufacturer’s recommended in-
tervals in the tire manufacturer’s warranty
pamphlet located in your vehicle literature
portfolio. If none is available, tires should
be rotated every 3 000 to 6 000 miles
(5 000 to 10 000 km), or sooner if neces-
sary, according to the degree of tire wear.
The same rotation (spinning) direction
must be maintained (
page 307).
Rotate tires before the characteristic tire
wear pattern becomes visible (shoulder
wear on front tires and tread center wear
on rear tires).
Thoroughly clean the mounting face of
wheels and brake discs, i.e. the inner side
of the wheels/tires, during each rotation.
Check for and ensure proper tire inflation
pressure.For information on wheel change, see the
“Practical hints” section (
page 392) and
(
page 408).
Warning!G
Rotate front and rear wheels only if the tires
are of the same dimension.
If your vehicle is equipped with mixed-size
tires (different tire dimensions front vs.
rear), tire rotation is not possible.
Warning!G
Have the tightening torque checked after
changing a wheel. Wheels could become
loose if not tightened with a torque of
80 lb-ft (110 Nm).
Only use genuine Mercedes-Benz wheel
bolts specified for your vehicle’s rims.

392 Practical hints
Where will I find...?
Tilt both plates upward1.
Fold the lower plate outward2.
Guide the tabs of the lower plate all the
way into the openings of the base
plate3.
For information on where to place wheel
chocks when changing a wheel, see
“Lifting the vehicle” (
page 414).
Spare wheel with collapsible tire
The spare wheel is located in the storage
compartment underneath the trunk floor.
1Spare wheel, spare wheel bolts
(located under plastic cover on the
outside of spare wheel rim)
2Vehicle tool kit (under spare wheel)
3Retaining screwOpen the trunk (page 99).
Lift up trunk floor.
Loosen retaining screw3by turning it
counterclockwise.
Remove spare wheel1.
Take off the wheel bolts for spare
wheel1.
Storing the spare wheel with
collapsible tire
If you wish to store the spare wheel after
use, carry out the following steps. Other-
wise the spare wheel will not fit the storage
compartment.
Unscrew the valve cap from the valve
of the collapsible tire.
Take the valve extractor from the vehi-
cle tool kit (
page 389).
!Make sure the collapsible tire is dry when
storing it.

393 Practical hints
Where will I find...?
Unscrew the valve insert from the valve
and allow the air to escape.
Screw the valve insert back into the
valve.
Screw the valve cap back on the valve.
Pull the protective wrap provided with
the vehicle tool kit over the spare
wheel.
Store the spare wheel and the valve
extractor in the storage compartment
underneath the trunk floor.
Pierce the protective wrap with retain-
ing screw3.
Secure the spare wheel by turning
retaining screw3 clockwise.
For information on mounting the spare
wheel, see “Flat tire” (
page 408).
Spare wheel bolts
1Wheel bolt for light alloy rims
2Wheel bolt for spare wheel with
collapsible tire (located under plastic
cover on the outside of spare wheel
rim)
iIt may take a few minutes for the collapsible
tire to deflate completely.
!Wheel bolts2 must be used when mount-
ing the spare wheel with collapsible tire. The use
of any wheel bolts other than wheel bolts2 for
the spare wheel with collapsible tire will physi-
cally damage the vehicle’s brakes.

414 Practical hints
Flat tire
Mounting the spare wheel
Preparing the vehicle
Prepare the vehicle as described
(
page 408).
Take the spare wheel, wheel wrench,
wheel bolts, jack, and electric air pump
out of the trunk (
page 389).Lifting the vehicle
Prevent the vehicle from rolling away
by blocking wheels with wheel chocks
or other sizeable objects.
One wheel chock is included with the
vehicle tool kit (
page 390).
When changing wheel on a level surface:
Place one wheel chock or other size-
able object in front of and another
wheel chock or other sizeable object
behind the wheel that is diagonally
opposite to the wheel being changed.
Always try lifting the vehicle using the jack
on a level surface. However, should cir-
cumstances require you to do so on a hill,
place the wheel chock or other sizeable
object and the other wheel chock or other
sizeable object as follows:
Place wheel chocks and other sizeable
objects on the downhill side blocking
both wheels of the axle not being
worked on.
Warning!G
The dimensions of the spare wheel are dif-
ferent from those of the road wheels. As a
result, the vehicle handling characteristics
change when driving with a spare wheel with
collapsible tire mounted. Adapt your driving
style accordingly.
The spare wheel is for temporary use only.
When driving with spare wheel mounted,
ensure proper tire inflation pressure
and do not exceed vehicle speed of
50 mph (80 km/h).
Drive to the nearest Mercedes-Benz Center
as soon as possible to have the spare wheel
replaced with a regular road wheel.
Never operate the vehicle with more than
one spare wheel mounted.
Do not switch off the ESP
® when a spare
wheel is mounted.

415 Practical hints
Flat tire
1Wheel wrench
On wheel to be changed, loosen but do
not yet remove the wheel bolts in direc-
tion of arrow (approximately one full
turn with wheel wrench1).
The jack take-up brackets are located di-
rectly behind the front wheel housings and
in front of the rear wheel housings.2Jack
3Take-up bracketPlace jack2 on firm ground.
Position jack2 under take-up
bracket3 so that it is always vertical
(plumb-line) as seen from the side,
even if the vehicle is parked on an
incline.
Warning!G
The jack is designed exclusively for jacking
up the vehicle at the jack take-up brackets
built into either side of 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
firmly set parking brake and block wheels
before raising vehicle with jack.
Do not disengage parking brake while the
vehicle is raised. Be certain that the jack is
always vertical (plumb line) when in use, es-
pecially on hills. Always try to use the jack
on level surface. Be sure the jack arm is fully
seated in the jack take-up bracket. Always
lower the vehicle onto sufficient capacity
jackstands before working under the
vehicle.
Warning!G
Position the jack only on the jack take-up
brackets designed for this purpose.
If the jack is not properly positioned, the
vehicle may fall off of the jack.


416 Practical hints
Flat tire
Jack up the vehicle until the wheel is a
maximum of 1.2 in (3 cm) from the
ground.Removing the wheel
4Alignment bolt
Unscrew the upper-most wheel bolt
and remove.
Replace this wheel bolt with alignment
bolt4 supplied in the vehicle tool
kit (
page 389).
Remove the remaining bolts.
Remove the wheel.Mounting the spare wheel
1Wheel bolt for light alloy rims
2Wheel bolt for spare wheel with
collapsible tire (located under plastic
cover on the outside of spare wheel
rim)
Warning!G
The jack is intended only for lifting the
vehicle briefly for wheel changes. It is not
suited for performing maintenance work
under the vehicle.

Never start the engine when the vehicle
is raised.

Never lie down under the raised vehicle.
!Do not place wheel bolts in sand or dirt. This
could result in damage to the bolt and wheel hub
threads.
Warning!G
Inflate collapsible tire only after the wheel is
properly mounted.
Inflate the collapsible tire using the electric
pump (
page 418) before lowering the
vehicle.


417 Practical hints
Flat tire
Clean contact surfaces of wheel and
wheel hub.
Guide the spare wheel onto the align-
ment bolt and push it on.
Insert the wheel bolts and tighten them
slightly.
!Wheel bolts2 must be used when mount-
ing the spare wheel with collapsible tire. The use
of any wheel bolts other than wheel bolts2 for
the spare wheel with collapsible tire will physi-
cally damage the vehicle’s brakes.
!To avoid paint damage, place wheel flat
against hub and hold it there while installing first
wheel bolt.
Warning!G
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 Mercedes-Benz Center or call
Roadside Assistance.
Incorrect wheel bolts or improperly tight-
ened wheel bolts can cause the wheel to
come off. This could cause an accident. Be
sure to use the correct wheel bolts.


418 Practical hints
Flat tire
Unscrew the alignment bolt, install last
wheel bolt and tighten slightly.
Inflate the collapsible tire
(
page 418).Inflating the collapsible tire
1Flap
2Air pump switch
3Electrical plug
4Air hose with pressure gauge and vent
screw
5Union nut
Take the electric air pump out of the
trunk (
page 390).
Open flap1 on air pump.
Pull out electrical plug3 and air hose
with pressure gauge4.
Close vent screw on air hose4.
Remove the valve cap from the tire
valve.
Screw union nut5 onto the tire valve.
Make sure electric air pump switch2
is set to0.
Insert electrical plug3 into the power
outlet in the passenger footwell
(
page 257).
Turn the SmartKey in the starter switch
to position1.
Warning!G
Use only genuine Mercedes-Benz 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.Warning!G
Observe instructions on air pump label.
!Do not lower the vehicle before inflating the
collapsible tire. Otherwise the rim may be
damaged.
!The cigarette lighter (page 256) is not de-
signed for use with the electric air pump. Use the
power outlet in the passenger footwell
(
page 257) for electric air pump operation.