wheel bolts MERCEDES-BENZ SLK320 2003 R170 Owner's Manual

180 OperationTires and wheels
Tires and wheelsSee your authorized Mercedes-Benz Cen-
ter for information on tested and recom-
mended rims and tires for summer and
winter operation. They can also offer ad-
vice concerning tire service and purchase.
Retread 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 your authorized Mercedes-Benz Cen-
ter for information on tested and recom-
mended rims and tires for summer and
winter operation.
Important guidelines

Use only 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.


If vehicle is heavily loaded, check tire
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 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 your 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, use only 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.

182 OperationTires and wheelsTire pressure changes by approximately
1.5 psi (0.1 bar) per 18°F (10°C) of air
temperature change. Keep this in mind
when checking tire pressure where the
temperature is different from the outside
temperature.
The tire temperature and with it the tire
pressure is increased also while driving,
depending on the driving speed and the
tire load.Check the spare tire periodically for condi-
tion and inflation. Spare tires will age and
b e c o m e w o r n o v e r t i m e e v e n i f n e v e r u s e d ,
and thus should be inspected and replaced
when necessary.
Rotating wheels
The wheels can be rotated every 3000 to
6000 miles (5 000 to 10000 km), or soon-
er if necessary, according to the degree of
tire wear. The same direction of tire rota-
tion must be retained.Rotate the wheels before the characteris-
tic tire wear pattern becomes visible
(shoulder wear on front wheels and tread
center wear on rear wheels).
Thoroughly clean the inner side of the
wheels after each rotation. Check and en-
sure proper tire inflation pressure.
Warning!
G
Follow recommended inflation pressure.
Do not overinflate tires. Overinflated tires
can result in sudden deflation (blowout) be-
cause they are more likely to become punc-
tured or damaged by road debris, potholes
etc.
Do not underinflate tires. Underinflated tires
wear unevenly, adversely affect handling
and fuel economy, and are more likely to fail
from being overheated.
Do not overload the tires by exceeding the
specified vehicle capacity weight (as indicat-
ed by the label on the pillar in the driver’s
door opening). Overloading the tires can
overheat them, possibly causing a blowout.Warning!
G
Rotate front and rear wheels only if they are
of the same size.
Warning!
G
Have the tightening torque checked after
changing a wheel. Wheels could become
loose if not tightened with a torque of
80 ft.lb. (110 Nm).
Use only genuine Mercedes-Benz wheel
bolts specified for your vehicle's rims.

206 Practical hintsWhere will I find ...?
Where will I find ...?First aid kit
The first aid kit is located on the left side of
the trunk.
1First aid kit
Loosen the fastening strap.

Remove first aid kit1.
Vehicle tool kit
The following is included:

Vehicle tool kit


Towing eye bolt


Wheel wrench


Alignment bolt


Vehicle jack


Wheel bolts


Special fuse puller
The jack is exclusively designed for lifting
the vehicle during a wheel change. Always
lower the vehicle on sufficient capacity
jackstands before working under the
vehicle.
iCheck expiration dates and contents
for completeness at least once a year
and replace missing/expired items.
Warning!
G
The jack is designed exclusively for jacking
up the vehicle at the jack tubes built into ei-
ther side of the vehicle. To help avoid per-
sonal 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 that the jack arm is
fully inserted in the jack tube. Always lower
the vehicle onto sufficient capacity jack-
stands before working under the vehicle.

207 Practical hints
Where will I find ...?
Vehicles with a spare wheel
(SLK 230 Kompressor, SLK 320)
1Spare wheel with collapsible tire
2Vehicle tool kit
3Wheel wrench
4Jack
5Electric air pump, bolts for spare wheel
rimSparewheel, vehicle tool kit, wheel
wrench, jack and electric air pump are
located under the trunk floor cover.

Lift trunk floor cover.
You can take out vehicle tool kit2,
wheel wrench3 and jack4.
Electric air pump5 is secured with a belt.

Loosen the belt.

Remove electric air pump from pump
holder.
Spare wheel1 is secured with the pump
holder.

Turn pump holder counterclockwise.

Remove pump holder.

Remove spare wheel out of the wheel
well.Spare wheel bolts
Wheel bolts1 Wheel bolt for

wheel rim size 7Jx16 H2 and 8Jx16 H2


AMG wheel rim size 7
1⁄2Jx17 H2 and
8
1⁄2Jx17 H2


spare wheel rim size 4
1⁄2Bx16 H2
2 Wheel bolt for


spare wheel rim size 4
1⁄2Bx15 H2
(located with electric air pump)

208 Practical hintsWhere will I find ...?More information can be found in the
“Technical data” section (
page 265).Vehicles with TIREFIT kit (SLK 32 AMG)
1Electric air pump
2TIREFIT kit
3Vehicle tool kit, jack, wheel wrenchThe electric air pump and TIREFIT kit are
located in the storage box under the trunk
floor cover.
The vehicle tool kit, jack and wheel wrench
are located below the rug on the right side.

Lift trunk floor cover.

Open storage box cover.
You can take out vehicle tool kit3 and
accessories.

Pull down the flap on the storage box.

Remove electric air pump1 and
TIREFIT kit2.
!Wheel bolts2 must be used when
mounting spare wheel rim size
41⁄2Bx15 H2.
The use of any wheel bolts other than
wheel bolts2 for spare wheel rim size
4
1⁄2Bx15 H2 can cause physical dam-
age to the vehicle.
Warning!
G
Be sure to use original length wheel bolts
when remounting the original wheel after it
has been repaired.

239 Practical hints
Flat tire

On whee l to b e change d, loos en b ut do
not yet remove the wheel bolts (ap-
proximately one full turn with wrench).
The jack support tubes are located behind
the front wheel housings and in front of the
rear wheel housings.1Jack tube cover
2Notch

Carefully insert the screwdriver (sup-
plied in the tool kit) into notch2.

Pry out cover1 just so far as you can
place your fingers underneath the cov-
er.

Carefully pull out cover1 completely.
Make sure that the pins do not brake
off.
The cover will be hanging from a plastic
band attached to it.
Warning!
G
The jack is designed exclusively for jacking
up the vehicle at the jack tubes built into
both sides of the vehicle. To help avoid per-
sonal injury, use the jack only to lift the ve-
hicle 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. Make sure that the jack
arm is fully inserted in the jack tube. Always
lower the vehicle onto sufficient capacity
jackstands before working under the vehi-
cle.


240 Practical hintsFlat tire3Jacking pin
4Jack support tube hole
5Crank
6Small platform
7Large platform
Fold out jacking pin3 in direction of
arrowA until it snaps into place.
The green marking on the jacking pin
should now form one line with the
marking on the jack.

Insert jacking pin3 in direction of
arrowB fully into jack support tube
hole4.

Keeping jack in this position, turn
crank5 clockwise until the jack’s small
platform6 meets the ground. Make
sure that the jack is always vertical
(plumb line).

Jack the vehicle until the wheel is a
maximum of 1.2 in (3 cm) from the
ground.
The jack is now standing on large
platform7.
Never start engine while vehicle is
raised.Removing the wheel
1Alignment bolt

Unscrew upper-most wheel bolt and re-
move.

Replace this wheel bolt with alignment
bolt1 supplied in the tool kit.

Remove the remaining bolts.
Warning!
G
Insert the jack arm fully into the jack sup-
port tube hole up to the stop. Otherwise the
vehicle may fall from the jack and cause per-
sonal injury or damage to the vehicle.
!Do not place wheel bolts in sand or dirt.
This could result in damage to the bolt
and wheel hub threads.


241 Practical hints
Flat tire

Remove the wheel.

Take the spare tire out of the trunk.
Mounting the new wheel
Wheel bolts1 Wheel bolt for

wheel rim size 7Jx16 H2 and 8Jx16 H2


AMG wheel rim size 7
1⁄2Jx17 H2 and
8
1⁄2Jx17 H2


spare wheel rim size 4
1⁄2Bx16 H2
2 Wheel bolt for


spare wheel rim size 4
1⁄2Bx15 H2
(located with electric air pump)

Clean contact surfaces of wheel and
wheel hub.

Guide the spare wheel onto the align-
ment bolt and push it on.

Insert wheel bolts and tighten them
slightly.

Inflate the spare tire using the electric
air pump (
page 243).
!Wheel bolts2 must be used when
mounting spare wheel rim size
41⁄2Bx15 H2.
The use of any wheel bolts other than
wheel bolts2 for spare wheel rim size
4
1⁄2Bx15 H2 can cause physical dam-
age to the vehicle.
Warning!
G
Be sure to use original length wheel bolts
when remounting the original wheel after it
has been repaired.
Warning!
G
Inflate spare wheel with collapsible tire only
after the wheel is properly mounted.!To avoid paint damage, place wheel flat
against hub and hold it there while in-
stalling first wheel bolt.


242 Practical hintsFlat tire

Unscrew the alignment bolt, install last
wheel bolt and tighten slightly.
Lowering the vehicle

Lower vehicle by turning crank coun-
terclockwise until vehicle is resting ful-
ly on its own weight.

Pull the jack out of the jack support
tube.

Remove jack tube cover.1-5Wheel bolts

Tighten the five wheel bolts evenly, fol-
lowing the diagonal sequence illustrat-
ed (1to5), until all bolts are tight.
Observe a tightening torque of 80 ft lb
(110 Nm).
Warning!
G
Always replace wheel bolts that are dam-
aged or rusted.
Never apply oil or grease to wheel bolts.
Damaged wheel hub threads should be re-
paired immediately. Do not continue to drive
under these circumstances! Contact an au-
thorized Mercedes-Benz Center or call
Roadside Assistance.
Incorrect mounting bolts or improperly
tightened mounting bolts can cause the
wheel to come off. This could cause an acci-
dent. Be sure to use the correct mounting
bolts.
Warning!
G
Use only genuine equipment
Mercedes-Benz wheel bolts. They are identi-
fied by the Mercedes star. Other wheel bolts
may come loose.
Do not tighten the wheel bolts when the ve-
hicle is raised. Otherwise the vehicle could
tip over.
Warning!
G
Have the tightening torque checked after
changing a wheel. The wheels could come
loose if they are not tightened to a torque of
80 ft lb (110 Nm).


282 Technical termsRetractable hardtop
Hardtop that can be opened and closed
at the push of a button and stored in
the trunk.
Roll bar
Occupant protection system which
consists of tubular steel sheathed in
plastic.
RON
(R
esearch O
ctane N
umber)
The Research Octane Number for gaso-
line as determined by a standardized
method. It is an indication of a gaso-
line's ability to resist undesired detona-
tion (knocking). The average of both
the ->MON (Motor Octane Number)
and RON (Research Octane Number) is
posted at the pump, also known as
ANTI-KNOCK INDEX.Shift lock
When the vehicle is parked, this lock
prevents the transmission selector le-
ver from being moved out of positionP
without key turned and brake pedal de-
pressed.
SRS
(S
upplemental R
estraint S
ystem)
Seat belts, emergency tensioning de-
vice and airbags. Though independent
systems, they are closely interfaced to
provide effective occupant protection.
Tele Aid System
(T
elematic A
larm I
dentification on
D
emand)
The Tele Aid system consists of three
types of response: automatic and man-
ual emergency, roadside assistance
and information. Tele Aid is initially ac-
tivated by completing a subscriber
agreement and placing an acquain-
tance call.The Tele Aid system is operational pro-
viding that the vehicle’s battery is
charged, properly connected, not dam-
aged and cellular and GPS coverage is
available.
Tightening torque
Force times lever arm (e.g. a lug
wrench) with which threaded fasteners
such as wheel bolts are tightened.
TIREFIT
Accessory for emergency and tempo-
rary tire repair. The TIREFIT kit consists
of a container with sealant material, a
filler hose, a valve stem tool, a valve in-
sert, and an air compressor.