Jaguar S-Type. Manual — part 51

Tires

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Incorrect wheel alignment will accelerate
tire wear. If there is wear on the inner or
outer edges of the tread pattern it will be
advantageous to have the cause detected
by having the wheel alignment checked.

Do not interchange tires from side to side,
front to rear or vice versa.

Note:

•

On certain models, the rear wheel and
tire assemblies will be larger than the
front. These larger assemblies must
never be fitted to the front of the
vehicle.

•

On certain models, the tires specified
may be of a directional type. These
tires must be fitted so that when
viewed from the side of the vehicle,
the tire direction of rotation arrow will
point in the vehicle forward direction
of travel, when positioned at the top of
the tire.

Tire repair

It is recommended that damaged tires are
discarded and new tires fitted. They must
not be repaired in view of the high
performance capability of the vehicle.

Damage

Excessive local distortion can cause the
casing of a tire to fracture and may lead to
premature failure. Tires should be
examined especially for cracked walls,
exposed cords, etc. Flints and other
sharp objects must be removed from the
tire tread; if left in they may work through
the cover. Clean off any oil or grease
contamination by using a suitable cleaner.

Caution: Do not use paraffin
(kerosene), because this has a
detrimental effect on rubber.

Tire use after vehicle storage

After a long period of a vehicle standing,
tires may become locally distorted with a
flat area. This will cause an uneven ride
for a few miles until the tires have warmed
up and the flat area rounds off.

However, to reduce the effects of flat
spots, the tires of a stored vehicle may be
inflated to pressures not
exceeding 420 kPa (60 psi).

Tire ageing

Tires degrade over time, even when they
are not being used. It is recommended
that tires generally be replaced after six
years of normal service. Heat caused by
hot climates or frequent high loading
conditions can accelerate the ageing
process.

You should replace the spare tire when
you replace the other road tires due to the
ageing of the spare tire.

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Tires

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TIRE QUALITY GRADES

United States Department of
Transportation - Uniform Tire Quality
Grades

The following information relates to the
tire grading system developed by the
National Highway Traffic Safety
Administration which will grade tires by
tread wear, traction and temperature
performance.

Note: Tires that have deep tread and
winter tires are exempt from these
marking requirements.

Quality grades, where applicable, can be
found on the tire sidewall between the
tread shoulder and maximum section
width.

For example:

Tread wear

The tread wear grade is a comparative
rating based on the wear rate of the tire
when tested under controlled conditions
on a specified government test course.
For example, a tire graded 150 would
wear one and a half (1.5) times as well on
the government course as a tire
graded 100.

The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly
from the norm due to variations in driving
habits, service practices and differences
in road characteristics and climate.

Traction

The traction grades, from the highest to
the lowest are AA, A, B and C. The
grades represent the tire’s ability to stop
on wet pavement as measured under
controlled conditions on specified
government test surfaces of asphalt and
concrete. A tire marked C may have poor
traction performance.

!

WARNING:

The traction grade assigned to this tire
is based on straight ahead braking
traction tests and does not include
acceleration, cornering, hydroplaning,
or peak traction characteristics.

Temperature - A, B, C

The temperature grades are A
(the highest), B and C, representing the
tire’s resistance to the generation of heat
and its ability to dissipate heat when
tested under controlled conditions on a
specified indoor laboratory test wheel.

Sustained high temperature can cause
the material of the tire to degenerate and
reduce tire life, and excessive
temperature can lead to sudden tire
failure.

The grade C corresponds to a level of
performance which all passenger car tires
must meet under the Federal Motor
Vehicle Safety Standard No. 109.

Grades B and A represent higher levels of
performance on the laboratory test wheel
than the minimum required by law.

Treadwear 200

Traction AA

Temperature A

Tires

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L

!

WARNING:

The temperature grade for these tires
is established for a tire that is properly
inflated and not overloaded. Excessive
speed, under-inflation or excessive
loading, either separately or in
combination, can cause heat build-up
and possible tire failure.

TIRE RENEWAL

When renewing tires, it is preferable to fit
a complete vehicle set. If either front or
rear tires only need to be renewed,
new tires must be fitted, as axle sets,
to replace worn ones.

After new tires have been fitted the
wheels need to be dynamically balanced.

The radial ply tires specified are designed
to meet the high-speed performance
capability of this vehicle.

Do not fit tires with a different tread
pattern, size or speed rating.

Caution: Ultra High Performance Tires.

This vehicle is equipped with a Ultra
High Performance Tire and wheel
combination designed to provide
maximum dry pavement performance
with consideration for hydroplaning
resistance. As such, they may be more
susceptible to road hazards and
consequential damage. Ultra High
Performance Tires may also be
expected to experience increased
tread wear with shorter tread life.

These tires are not recommended for
driving on snow or ice, and should be
replaced with winter tires, when
weather conditions dictate.

SNOW CHAINS

Snow chains, of the recommended type,
may only be fitted to rear wheels.

Contact your Jaguar Dealer for details
and availability of approved snow chains.

The maximum speed when using snow
chains is 48 km/h (30 mph).

Remove the snow chains immediately the
roads are clear of snow.

Ensure the fitting instructions supplied
with the snow chains are kept in a safe
place, for example, with this literature
pack.

Note: Dynamic Stability Control MUST be
switched OFF when using snow chains.

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Tire Glossary

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Tire Glossary

GLOSSARY

Cold tire pressure:

Pressure in a tire that has been driven for
less than one mile or has been standing
for three hours or more.

Maximum inflation pressure:

Maximum air pressure, to which a cold
tire may be inflated, this figure (in kPa and
psi) is moulded onto the sidewall of a tire.

Curb weight:

The weight of a motor vehicle with
standard equipment including the
maximum capacity of fuel, oil, coolant
and if so equipped, air conditioning and
additional weight optional engine.

Accessory weight:

The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power
seats, radio and heater, to the extent that
these items are available as
factory-installed equipment (whether
installed or not).

Production options weight:

The combined weight of those installed
production options weighing over 1.4 kg
(3 lb) in excess of those standard items
which they replace, not previously
considered in curb weight or accessory
weight, including heavy duty brakes, ride
levellers, roof rack, heavy duty battery
and special trim.

Vehicle capacity weight:

The rated cargo and luggage load plus
68.0 kg (150.0 lb) times the vehicle’s
designated seating capacity.

Maximum loaded vehicle weight:

This is the sum of:
• Curb weight.
• Accessory weight.
• Vehicle capacity weight.
• Production options weight.

Rim:

A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated.

Bead:

The part of the tire that is made of steel
wires, wrapped or reinforced by ply cords
and that is shaped to fit the rim.