250Wheels and tyres
Wheel bolts
Wheel bolts must be tightened to the correct torque.
The design of wheel bolts is matched to the rims. If different wheel rims are
fitted, the correct wheel bolts with the right length and correctly shaped
bolt heads must be used. This ensures that wheels are fitted securely and
that the brake system functions correctly.
In certain circumstances, you should not use wheel bolts from a different
vehicle, even if it is the same model ⇒ page 222.
After the wheels have been changed, the tightening torque of the wheel
bolts should be checked as soon as possible with a torque wrench. ⇒
The tightening torque for steel and alloy wheels is 120 Nm.
WARNING
If the wheel bolts are not tightened correctly, the wheel could become
loose while driving. Risk of accident.
● The wheel bolts must be clean and turn easily. Never apply grease or
oil to them.
● Use only wheel bolts which belong to the wheel.
● If the tightening torque of the wheel bolts is too low, they could loos-
en whilst the vehicle is in motion. Risk of accident! If the tightening tor-
que is too high, the wheel bolts and threads can be damaged.
CAUTION
The prescribed tightening torque for wheel bolts for steel and alloy wheels
is 120 Nm. Winter tyres
Winter tyres will improve the vehicles handling on snow and
ice.
In winter conditions winter tyres will considerably improve the vehicle's han-
dling. The design of summer tyres (width, rubber compound, tread pattern)
gives less grip on ice and snow.
Winter tyres must be inflated to a pressure 0.2 bar higher than the pres-
sures specified for summer tyres (see sticker on fuel tank flap).
Winter tyres must be fitted on all four wheels.
Information on permitted winter tyre sizes can be found in the vehicle's reg-
istration documentation. Use only radial winter tyres. All tyre sizes listed in
the vehicle documentation also apply to winter tyres.
Winter tyres lose their effectiveness when the tread is worn down to a depth
of 4 mm.
The speed rating code ⇒ page 248, New tyres and wheels determines the
following speed limits for winter tyres: ⇒
max. 160 km/h (100 mph)
max. 180 km/h (110 mph)
max. 190 km/h (118 mph)
max. 210 km/h (130 mph)
In some countries, vehicles which can exceed the speed rating of the fitted
tyre must have an appropriate sticker in the driver's field of view. These
stickers are available from your Technical Service. The legal requirements of
each country must be followed.
Do not have winter tyres fitted for unnecessarily long periods. Vehicles with
summer tyres handle better when the roads are free of snow and ice.
Q
S
T
H
255
If and when
Note
Please observe legal requirements when doing so.
Changing a wheel
Change the wheel as described below.
– Remove the wheel cover .
– Loosen the wheel bolts ⇒ page 256.
– Raise the vehicle with the jack ⇒ page 257.
– Take off the wheel with the flat tyre and then put on the spare
wheel ⇒ page 258.
– Lower the vehicle.
– Tighten the wheel bolts firmly in diagonal sequence with the
box spanner ⇒ page 256.
– Replace the cover.
After changing a wheel
After changing the wheel, there are still tasks to complete. – Place the wheel with the defective tyre in the spare wheel well
and secure it.
– Put the tools and jack back in the luggage compartment. –
The inflation pressure of the newly fitted spare tyre must be
checked as soon as possible.
– Have the tightening torque of the wheel bolts checked as soon
as possible with a torque wrench. It must be 120 Nm (always
when cold)
– Have the flat tyre replaced as quickly as possible.
Note
● If you notice that the wheel bolts are rusty and difficult to turn when
changing a wheel, they must be replaced before having the tightening tor-
que checked.
● For safety reasons, drive at moderate speeds until the wheel bolt tight-
ening torque has been checked.
Safety FirstOperating instructionsPractical TipsTechnical Specifications
296Description of specifications
Towing a trailer
Trailer weights
Trailer weight
The trailer weights and drawbar loads approved are selected in intensive tri-
als according to precisely defined criteria. The approved trailer weights are
valid for vehicles in the EU for maximum speeds of 80 km/h (50 mph) (in
certain circumstances up to 100 km/h (60 mph). The figures may be differ-
ent in other countries. All data in the official vehicle documentation takes
precedence over these data at all times ⇒
.
Drawbar loads
The maximum permitted drawbar load on the ball joint of the towing bracket
must not exceed 75 kg.
In the interest of road safety, we recommend that you always tow approach-
ing the maximum drawbar load. The response of the trailer on the road will
be poor if the drawbar load is too small.
If the maximum permissible drawbar load cannot be met (e.g. with small,
empty and light-weight single axle trailers or tandem axle trailers with a
wheelbase of less than 1 metre), a minimum of 4% of the actual trailer
weight is legally required for the drawbar load.
WARNING
● For safety reasons, do not exceed the 80 km/h (50 mph) limit. This is
also valid in countries where higher speeds are permitted.
● Never exceed the maximum trailer weights or the drawbar load. If the
permissible axle load or the permissible total weight is exceeded, the
driving characteristics of the vehicle may change, leading to accidents,
injuries and damage to the vehicle.
Wheels
Tyre pressure, snow chains, wheel bolts
Tyre pressures
The sticker with the tyre pressure values can be found on the inside of the
fuel tank flap. The tyre pressure values given there are for cold tyres. The
slightly raised pressures of warm tyres must not be reduced. ⇒
Snow chains
Snow chains may be fitted only to the front wheels.
Consult the section “wheels” of this manual.
Wheel bolts
After the wheels have been changed, the tightening torque of the wheel
bolts should be checked as soon as possible with a torque wrench ⇒
.
The tightening torque for steel and alloy wheels is 120 Nm.
WARNING
● Check the tyre pressure at least once per month. Checking the tyre
pressure is very important. If the tyre pressure is too high or too low,
there is an increased danger of accidents, particularly at high speeds.
● If the tightening torque of the wheel bolts is too low, they could loos-
en while the vehicle is in motion. Risk of accident! If the tightening tor-
que is too high, the wheel bolts and threads can be damaged.
Note
We recommend that you ask your Technical Service for information about
appropriate wheel, tyre and snow chain size.
Stopping the engine . . . . . . . . . . . . . . . . . . . . 168
Sun visors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
Switches on the driver doorElectric windows . . . . . . . . . . . . . . . . . . . . . 110
Symbols Red symbols in central display . . . . . . . . . . 78
Yellow symbols on central display . . . . . . . 80
T Technical modifications . . . . . . . . . . . . . . . . . . 222
The danger of not using the seat belt . . . . . . . . 20
The environment Heated rear window . . . . . . . . . . . . . . . . . . 126
Leaks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228
Warming up the engine . . . . . . . . . . . . . . . 167
Tightening torque of wheel bolts . . . . . . . . . . 296
tiptronic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180
tiptronic mode . . . . . . . . . . . . . . . . . . . . . . . . . 185
Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
Tow-starting . . . . . . . . . . . . . . . . . . . . . . . . . . . 290
Towing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200, 290 Accessories . . . . . . . . . . . . . . . . . . . . . . . . . 202
Notes on towing . . . . . . . . . . . . . . . . . 200, 201
Removable towing bracket . . . . . . . . . . . . 203
Technical requirements . . . . . . . . . . . . . . . 200
Towing a trailer . . . . . . . . . . . . . . . . . . . . . . . . . 296
Towing bracket, fitting . . . . . . . . . . . . . . . . . . . 208
Towing eyes . . . . . . . . . . . . . . . . . . . . . . . . . . . 291
Towline anchorage . . . . . . . . . . . . . . . . . . . . . . 290
Tow starting General notes . . . . . . . . . . . . . . . . . . . . . . . 290 Traction control system
How the system works . . . . . . . . . . . . . . . . 190
Traction control system (ASR) control lamp . . . . . . . . . . . . . . . . . . . . . . . . . 69
Trailer weights . . . . . . . . . . . . . . . . . . . . . . . . . 296
Trip recorder . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Turn signal lamps Hazard warning lights . . . . . . . . . . . . . . . . . 69
Trailer turn signals . . . . . . . . . . . . . . . . . . . . 67
Turn signals . . . . . . . . . . . . . . . . . . . . . . . . . 69
Turn signals . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Tyre mobility system . . . . . . . . . . . . . . . . . . . . . 253
Tyre Mobility System . . . . . . . . . . . . . . . . . . . . 259
Tyre pressure . . . . . . . . . . . . . . . . . . . 67, 91, 242 Loss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
Tyre pressure monitoring . . . . . . . . . . . . . . . . . 243
Tyre pressure monitoring system . . . . . . . . . . . 90
Tyre pressures . . . . . . . . . . . . . . . . . . . . . . . . . . 296
Tyre repair kit Tyre Mobility System . . . . . . . . . . . . . . . . . 259
Tyres and wheels Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . 248
Tyres tread depth . . . . . . . . . . . . . . . . . . . . . . . 246
Tyres useful life . . . . . . . . . . . . . . . . . . . . . . . . . 246
Tyres with directional tread pattern . . . . . . . . 242
U Underbody protection . . . . . . . . . . . . . . . . . . . 215
Upholstery Treating your upholstery . . . . . . . . . . . . . . 217 V
Vehicle care Treating your upholstery . . . . . . . . . . . . . . 217
Vehicle data . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
Vehicle identification data . . . . . . . . . . . . . . . . 294
Vehicle identification number . . . . . . . . . . . . . 294
Vehicle keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Vehicle maintenance electrically adjustable seats . . . . . . . . . . . 218
heated seats . . . . . . . . . . . . . . . . . . . . . . . . 218
natural leather . . . . . . . . . . . . . . . . . . . . . . 219
non-electrically adjustable seats . . . . . . . 218
seats with airbag components . . . . . . . . . 218
seats without airbag components . . . . . . 218
synthetic leather . . . . . . . . . . . . . . . . . . . . 220
trim fabrics . . . . . . . . . . . . . . . . . . . . . . . . . 218
unheated seats . . . . . . . . . . . . . . . . . . . . . . 218
Vehicle modifications . . . . . . . . . . . . . . . . . . . 222
Vehicle paintwork Maintenance . . . . . . . . . . . . . . . . . . . . . . . . 212
Products for vehicle maintenance . . . . . . . 210
Vehicle washing . . . . . . . . . . . . . . . . . . . . . . . . 211
Ventilation slits . . . . . . . . . . . . . . . . . . . . . . . . . 17
W
Warning lamp Alternator . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Warning lamps Airbag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Anti-lock brake system . . . . . . . . . . . . . . . . . 68
Electronic differential lock . . . . . . . . . . . . . . 68
314 Index
Engine management (EPC) . . . . . . . . . . . . . 70
Exhaust emission control system . . . . . . . . 66
Handbrake . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Red symbols in central display . . . . . . . . . . 78
Seat belt warning lamp . . . . . . . . . . . . . . . . 68
Yellow symbols on central display . . . . . . . 80
Warning lamps - overview . . . . . . . . . . . . . . . . . 65
Washer fluid level . . . . . . . . . . . . . . . . . . . . . . . . 82
Washing by hand . . . . . . . . . . . . . . . . . . . . . . . 211
Washing the vehicle . . . . . . . . . . . . . . . . . . . . . 211
Washing with high pressure cleaners . . . . . . . 212
Wear indicators . . . . . . . . . . . . . . . . . . . . . . . . 246
Wearing suitable shoes . . . . . . . . . . . . . . . . . . . 16
Wheel bolts . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296 Tightening torque . . . . . . . . . . . . . . . . . . . . 250
Wheels . . . . . . . . . . . . . . . . . . . . . . . . . . . 242, 296 Changing a wheel . . . . . . . . . . . . . . . . . . . 254
Why assume the correct sitting position? . . . . . 28
Why should head restraints be correctly adjus- ted? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Why wear seat belts? . . . . . . . . . . . . . . . 18, 19, 28
Windows Defrosting . . . . . . . . . . . . . . . . . . . . . . . . . . 159
Windscreen washer system . . . . . . . . . . . . . . . 235
Windscreen wiper blades Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
Windscreen wipers . . . . . . . . . . . . . . . . . . . . . . 128 Changing blades . . . . . . . . . . . . . . . . . . . . 236
Rain sensor . . . . . . . . . . . . . . . . . . . . . . . . . 128
Washer jets . . . . . . . . . . . . . . . . . . . . . . . . . 128
Winter Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238 Winter conditions
Defrost function . . . . . . . . . . . . . . . . . . . . . 159
Winter driving Diesel engine . . . . . . . . . . . . . . . . . . . . . . . 227
Winter operation Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
Winter tyres . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250
Wiper and washer system . . . . . . . . . . . . . . . . 128
Wooden trim cleaning . . . . . . . . . . . . . . . . . . . 220
315
Index