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
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