Jaguar S-Type. Manual — part 49

Tire Pressures

204

L

Recommended tire pressures

The following table gives the tire
pressures for all recommended tire sizes:

Checking tire pressures

The following procedure should be used
to check and adjust the tire pressures:

1. Remove the valve cover.

2. Firmly attach a tire pressure gauge or

inflator to the valve.

3. Read the tire pressure from the

gauge. If required, add air to the tire.

4. If air is added to the tire, remove the

gauge from the valve and re-attach it
before checking that the pressure is
correct. Failure to remove and
re-attach the gauge from the valve
could cause the gauge to show an
incorrect reading.

5. If too much air is added, remove the

gauge from the valve and allow air out
of the tire by pressing the center of the
valve. Reconnect the gauge to the
valve, and check that the air pressure
is correct.

6. Refit the valve cover.

A slight natural pressure loss occurs with
time. If this exceeds 14 kPa (2 psi) per
week, the cause should be investigated
and rectified.

Note: It is an offence in certain countries
to drive a vehicle with tires that are not
inflated in accordance with the vehicle’s
proper use.

Tire Size

Tire Pressure

Front

Rear

235/50 R17

220 kPa (32 psi)

220 kPa (32 psi)

245/40 R18

240 kPa (35 psi)

240 kPa (35 psi)

245/40 R18 S/C

280 kPa (40 psi)

-

275/35 R18 S/C

-

280 kPa (40 psi)

245/35 R19 S/C

255 kPa (37 psi)

-

275/30 R19 S/C

-

269 kPa (39 psi)

Space-saver spare wheel (front or rear)

420 kPa (60 psi)

205

Tire Pressures

R

Ambient temperature pressure
compensation

If the intended journey will take the vehicle
into an area where the ambient local
temperature is known to be lower than the
journey start point, tire pressure under

inflation could occur.

A colder ambient local temperature will
reduce pressure within the tire. An effect
is to decrease sidewall height and to
increase tire shoulder wear with the
potential for tire failure. Vehicle dynamics
could also be adversely affected.

In order to minimise this effect, tire
pressures can be adjusted to
compensate before the start of the
journey. Alternatively, tire pressures can
be adjusted when the area of lower
ambient temperature is reached.

In this situation the vehicle must be left in
the ambient local temperature for at least
one hour before tire pressure is adjusted.
To compensate for colder ambient
temperatures, tire pressures should be
increased by 2lbf/in

2

(0.14 bar / 14 kPa)

for each 10°C (20°F) decrease.

Note: Ensure that correct tire pressures
are maintained when moving to areas of
differing ambient temperature.

In areas of extended high ambient
temperature, vehicle tires can be affected
by a softening of the tire sidewall. If the
vehicle is stationary for long periods, the
effect is to slightly deform the tire at the
point where the tire meets the standing
surface. This is known as a flat spot.

This is normal tire behaviour, however,
when the vehicle is subsequently driven,
vibration may be experienced from the flat
spot. The condition will steadily improve
with additional mileage.

In order to minimise this effect, tire
pressures can be adjusted to
compensate.

For each 10°C (20°F) increase in
temperature above 20°C (68°F), tire
pressure should be increased by 2lbf/in

2

psi (0.14 bar / 14 kPa).

JOL4681

JOL4683

Tire Pressures

206

L

Tire pressure compensation
chart - high ambient
temperatures

WINTER (SNOW) TIRES

The tires fitted as original equipment are
designed with a rubber compound, tread
pattern and width specially suited for high
speeds in normal road conditions,
but they are less suitable during extremes
of low temperatures, snow and ice.

The use of winter tires will considerably
improve the vehicle’s handling during
these conditions

It is recommended that only Jaguar
approved winter tires are used,
as follows:

Winter 17 inch wheels

Pirelli Winter 240 Snowsport 235/50R17
100H

Continental TS810 235/50R17 100V.

Continental TS810 245/4517 99V.

The recommended tire pressures for
winter tires are the same as shown on
page 204.

Winter 18 inch wheels for Sport
derivatives

Pirelli Winter Snowsport 245/40R18 93H

Winter 18 inch wheels for
Supercharged vehicle

Pirelli Winter 240 Snowsport 235/40R18
95V X/L

Pirelli Winter 240 Snowsport 265/35R18
95V X/L

Winter 18 inch tire pressures:

Tire directional indicators must be
rotating in a clockwise direction when
viewed from the right-hand side of the
vehicle, and counter-clockwise when
viewed from the left-hand side of the
vehicle.

Do not exceed 130 mph (210 km/h) when
using H rated tires and 240 km/h (149
mph) when using V rated Jaguar
approved winter tires.

Winter tires must be used in vehicle sets,
that is: fitted on all four wheels.

If non-Jaguar approved winter tires are
fitted, refer to the tire pressure
information label, attached to the driver’s
side door front pillar (Canada and Mexico)
or the pillar behind the driver’s door
(USA).

Tire Pressure Temperature

Compensation

Ambient

Temperature °C

(°F)

Pressure

Compensation

lbf/in

2

(bar/kPa)

20 (68)

use placard label

30 (86)

+2 (0.14/14)

40 (104)

+4 (0.28/28)

50 (122)

+6 (0.41/41)

Up to 160 km/h (100 mph)

Front
(235)

207 kPa (30 psi)

Rear
(265)

230 kPa (34 psi)

Over 160 km/h (100 mph)

Front
(235)

260 kPa (38 psi)

Rear
(265)

290 kPa (42 psi)

207

Tires

R

Tires

TIRE MARKINGS

P (1)

The P indicates the tire is for passenger
vehicles.

Tire width (2)

This three-digit number gives the width in
millimetres of the tire from sidewall edge
to sidewall edge. In general, the larger the
number, the wider the tire.

Aspect ratio (3)

This two-digit number, known as the
aspect ratio, gives the tire's ratio of height
to width (this is also known as the tire
profile). The lower the number, the shorter
the tire’s sidewall.