Volvo XC90 2007 Owner's Manual download pdf (Page 153)

07 Wheels and tyres

152

General

07

Driving characteristics and tyres

The tyres greatly affect the car’s driving char-

acteristics. The type of tyre, dimensions, tyre

pressure and speed rating are important for

how the car performs.

When changing tyres, ensure that tyres of the

same type and dimensions, and preferably

also the same make, are fitted to all four

wheels. Follow the recommended tyre pres-

sures specified on the tyre pressure label,

see page 155.

Designation of dimensions

The dimensions are stated on all car tyres.

Example of designation: 225/70R16 102 H.

Speed ratings

The car has "Whole Vehicle Type Approval",

which means that dimensions and speed rat-

ings must not differ from those specified on

the vehicle’s registration document. The only

exception to these conditions is winter tyres

(both those with studs and those without). If

such a tyre is chosen, the car must not be

driven faster than the speed rating of the tyre

(for example, class Q can be driven at a max-

imum of 160 km/h).

Remember that traffic regulations determine

how fast a car can be driven, not the speed

class of the tyres.

Note! Maximum permitted speeds indicated.

New tyres

Tyres are perishable. After a

few years they begin to

harden at the same time as

the friction capacity/char-

acteristics gradually deteri-

orate. Therefore aim to get

as fresh tyres as possible

when you replace them. This is especially im-

portant with regard to winter tyres. The week

and year of manufacture, the tyre’s DOT

marking (Department of Transportation), are

stated with four digits, for example 1502. The

tyre in the illustration was manufactured in

week 15 of 2002.

Tyre age

All tyres older than six years should be

checked by an expert even if they seem un-

damaged. The reason for this is that tyres

age and decompose, even if they are hardly

ever or never used. The function can there-

fore be affected due to the tyre’s constituent

materials being broken down. In such a case

the tyre should then not be used. This also

applies to spare tyres, winter tyres and tyres

saved for future use. Examples of external

signs which indicate that the tyre is unsuita-

ble for use are cracks or discoloration.

The age of the tyre can be determined by the

DOT marking, see illustration above.

225 Section width (mm)

70 Ratio between section height and

width (%)

R Radial ply

16 Rim diameter in inches (")

102 Tyre load index (in this case 615 kg)

H Speed rating (in this case 270 km/h).

Q 160 km/h (used only on winter tyres)

T 190 km/h

H 210 km/h

V 240 km/h

W 270 km/h

Y 300 km/h

1 2 ... 148 149 150 151 152 153 154 155 156 157 158 ... 262 263

Comments to this Manuals

No comments