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181 Emission control
Technical
data Instruments 
and controlsOperationDrivingInstrument 
cluster displayPractical hints Car care Index Emission control
Certain systems of the engine serve to keep the toxic 
components of the exhaust gases within permissible 
limits required by law.
These systems, of course, will function properly only 
when maintained strictly according to factory 
specifications. Any adjustments on the engine should, 
therefore, be carried out only by qualified Mercedes-
B e n z  a ut h o r i z e d  c e n te r  te ch n i c i a n s .  E n g i n e  a d j u st m e n t s  
should not be altered in any way. Moreover, the 
specified service jobs must be carried out regularly 
according to Mercedes-Benz servicing requirements. 
For details refer to the Service Booklet.
Wa r n i n g !
Inhalation of exhaust gas is hazardous to your 
health. All exhaust gas contains carbon monoxide, 
and inhaling it can cause unconsciousness and 
lead to death.Do not run the engine in confined areas (such as a 
garage) which are not properly ventilated. If you 
think that exhaust gas fumes are entering the 
vehicle while driving, have the cause determined 
and corrected immediately. If you must drive under 
these conditions, drive only with at least one 
window fully open.
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        Page 265 of 346

262 Tires, Wheels
Technical
data Instruments 
and controlsOperation DrivingInstrument 
cluster displayPractical hintsCar care Index
Wheels
Replace rims or tires with the same designation, 
manufacturer and type as shown on the original part. 
See your authorized Mercedes-Benz Center for further 
information.
See your 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.
Tire replacement
Front tires should be replaced in sets. Rims and tires 
must be of the correct size and type. For dimensions, 
see “Technical Data” (page 314).
We recommend that you break in new tires for approx. 
60 miles (100 km) at moderate speed.It is imperative that the wheel mounting bolts be 
fastened to a tightening torque of 80 ft.lb. (110 Nm) 
whenever wheels are mounted.
For rim and tire specifications, refer to “Technical Data” 
(page 314).
Wa r n i n 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 result in 
the bolts loosening and possibly an accident.
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        Page 267 of 346

264 Tires, Wheels
Technical
data Instruments 
and controlsOperation DrivingInstrument 
cluster displayPractical hintsCar care Index
Spare wheel
Spare wheel CLK 320 (except Sport Package)
Important!
The spare wheel rim is mounted with a full size tire of 
the same type as on the vehicle, and is fully functional. 
However, that spare wheel rim is weight optimized and 
has a limited service life of 12 000 miles (20 000 km) 
use before a standard wheel rim must replace it.
In the case of a flat tire, you may temporarily use the 
spare wheel.
Do not operate vehicle with more than one spare wheel 
mounted.
Unidirectional tires must always be mounted with arrow 
on tire sidewall pointing in direction of vehicle forward 
movement.
If the arrow on tire side wall does not point in direction 
of vehicle forward movement when using the spare 
wheel, observe the following restriction:
•Drive to the nearest tire repair facility as soon as 
possible.For rim and tire specifications, refer to “Technical Data” 
(page 314).
Spare wheel CLK 320 (with Sport Package), 
CLK 430, CLK 55 AMG
Important!
The spare wheel rim size is 7
1/2J x 17 H 2.
The spare wheel rim is mounted with a full size tire of 
the same type as on the vehicle’s front axle (CLK 320 
with Sport Package: the tire size is 205/55 R 16 91 H), 
and is fully functional. However, the spare wheel rim is 
weight optimized and has a limited service life of 
12 000 miles (20 000 km) use before a standard wheel 
rim must replace it.
Wa r n i n g !
The spare wheel rim is for temporary use only. Use 
for over a total of 12 000 miles (20 000 km) 
(aggregate of all uses) may cause wheel rim failure 
leading to an accident and possible injuries.
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        Page 268 of 346

265 Tires, Wheels
Technical
data Instruments 
and controlsOperation DrivingInstrument 
cluster displayPractical hintsCar care Index If the arrow on tire side wall does not point in direction 
of vehicle forward movement when using the spare 
wheel, observe the following restriction:
•Drive to the nearest tire repair facility as soon as 
possible.
In the case of a rear axle flat tire (CLK 320 with Sport 
Package: In case of a flat tire), you may temporarily use 
the spare wheel, when observing the following 
restrictions:
•Do not exceed vehicle speed of 50 mph (80 km/h)
•Drive to the nearest tire repair facility to have the 
flat tire repaired or replaced as appropriate.
Do not operate vehicle with more than one spare wheel 
mounted.
Unidirectional tires must always be mounted with arrow 
on tire sidewall pointing in direction of vehicle forward 
movement.For rim and tire specifications, refer to “Technical Data” 
(page 314).
Wa r n i n g !
The spare wheel rim is for temporary use only. Use 
for over a total of 12 000 miles (20 000 km) 
(aggregate of all uses) may cause wheel rim failure 
leading to an accident and possible injuries.The dimensions of the spare wheel are different 
from those of the road wheels for the rear axle 
(CLK 320 with Sport Package: The dimensions of 
the spare wheel are different from those of the road 
wheels). As a result, the vehicle handling 
characteristics change when driving with a spare 
wheel mounted on the rear axle.The spare wheel should only be used temporarily, 
and replaced with a regular road wheel as quick as 
possible.
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        Page 277 of 346

274 Jump starting
Technical
data Instruments 
and controlsOperation DrivingInstrument 
cluster displayPractical hintsCar care Index
Jump startingImportant!
A discharged battery can freeze at approx. +14
°F 
(–10
°C). In that case, it must be thawed out before 
jumper cables are used. Attempting to jump start a 
frozen battery can result in it exploding, causing 
personal injury. 
Jumper cable specifications:
•Minimum cable cross-section of 25 mm
2 or approx. 
2AWG
•Maximum length of 11.5 ft. (3.5 m).
If the battery is discharged, the engine should be started 
with jumper cables and the (12 V) battery of another 
vehicle.
Only use 12 V battery to jump start your vehicle. Jump 
starting with more powerful battery could damage the 
vehicle’s electrical systems, which will not be covered 
by the Mercedes-Benz Limited Warranty.
The battery is located in the trunk under the trunk floor.
Wa r n i n g !
Failure to follow these directions will cause 
damage to the electronic components, and can lead 
to a battery explosion and severe injury or death.Never lean over batteries while connecting or jump 
starting, you might get injured.Battery fluid contains sulfuric acid. Do not allow 
this fluid to come in contact with eyes, skin or 
clothing. In case it does, immediately flush affected 
area with water, and seek medical help if 
necessary.A battery will also produce hydrogen gas, which is 
flammable and very explosive. Keep flames or 
sparks away from battery, avoid improper 
connection of jumper cables, smoking etc..Read all instructions before proceeding.
J_A208.book Seite 274 Donnerstag, 31. Mai 2001 9:35 09