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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!

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.