Jaguar XJ (2008 year). Manual - part 64

257

Wheels and Tires

R

Radio Frequency Approval

The TPMS transmitters and receivers 
comply with Part 15 of the FCC rules and 
RSS-210 of the industry Canada.

Operation is subject to the two following 
conditions:

1. The device may not cause harmful 

interference.

2. This device must accept any 

interference received, including 
interference that may cause 
undesired operation.

Note: Changes or modifications not 
expressly approved by the manufacturer 
could void the user’s authority to operate 
the equipment.

The TPMS radio frequency approval 
numbers for the USA and Canada are:

USA FCCID: KR5S120123, 
TX-KR55WK45057B RX-5WK4887.

Canada IC: 267T-S120123, 
267T-5WK47594, CAN2671032336A.

Wheels and Tires

258

L

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. 

R (4)

The R stands for radial. Radial ply 
construction of tires has been the industry 
standard for the past 20 years.

Wheel diameter (5)

This two-digit number is the wheel or rim 
diameter in inches. If you change your 
wheel size, you will have to purchase new 
tires to match the new wheel diameter.

Load index (6)

This two- or three-digit number is the 
tire's load index. It is a measurement of 
how much weight each tire can support. 

Note: You may not find this information 
on all tires because it is not required by 
law.

JAG0395N

1

2

3

4

5

6

7

9

10

11

12

13

14

15

8

259

Wheels and Tires

R

Speed rating (7)

The speed rating denotes the speed at 
which a tire is designed to be driven for 
extended periods of time. The ratings 
range from 99 miles per hour (mph) to 186 
mph. These ratings are listed in the 
following table. 

Note: You may not find this information 
on all tires because it is not required by 
law.

U.S DOT tire identification number (8)

This begins with the letters DOT and 
indicates that the tire meets all Federal 
standards. The next two numbers or 
letters are the plant code where it was 
manufactured, and the last four numbers 
represent the week and year the tire was 
built. For example, the numbers 3197 
means the 31st week of 1997. The other 
numbers are marketing codes used at the 
manufacturer's discretion. This 
information can be used to contact 
consumers if a tire defect requires a 
recall.

M+S (9)

The M+S or M/S indicates that the tire has 
some mud and snow capability. Most 
radial tires have these markings: they 
have some mud and snow capability.

Tire ply composition and materials 
used (10)

The number of plies indicates the number 
of layers of rubber-coated fabric in the 
tire. In general, the greater the number of 
plies, the more weight a tire can support. 
Tire manufacturers also must indicate the 
materials in the tire, which include steel, 
nylon, polyester, and others.

Treadwear number (11)

This number indicates the tire's wear rate. 
The higher the treadwear number is, the 
longer it should take for the tread to wear 
down. For example, a tire graded 400 
should last twice as long as a tire graded 
200. 

For more information, refer to page 263.

Letter Rating

Speed Rating

Q

99 mph

R

106 mph

S

112 mph

T

118 mph

U

124 mph

H

130 mph

V

149 mph

W

168 mph

Y

186 mph*

* For tires with a maximum speed 
capability over 149 mph, tire 
manufacturers sometimes use the 
letters ZR. For those with a maximum 
speed capability over 186 mph, tire 
manufacturers always use the letters 
ZR. 

Wheels and Tires

260

L

Traction letter (12)

This letter indicates a tire's ability to stop 
on wet pavement. A higher graded tire 
should allow you to stop your car on wet 
roads in a shorter distance than a tire with 
a lower grade. Traction is graded from 
highest to lowest as AA, A, B, and C. For 
more information, refer to page 263.

Maximum load rating (13)

This number indicates the maximum load 
in kilograms and pounds that can be 
carried by the tire.

Temperature letter (14)

This letter indicates a tire's resistance to 
heat. The temperature grade is for a tire 
that is inflated properly and not 
overloaded. Excessive speed, 
under-inflation or excessive loading, 
either separately or in combination, can 
cause heat build-up and possible tire 
failure. From highest to lowest, a tire's 
resistance to heat is graded as A, B, or C. 
For more information, refer to page 263.

Maximum permissible inflation 
pressure (15)

This number is the greatest amount of air 
pressure that should ever be put in the tire 
under normal driving conditions.

TIRE CARE

Tires of the correct type, manufacture and 
dimensions, with correct cold inflation 
pressures are an integral part of every 
vehicle’s design. Regular maintenance of 
tires contributes not only to safety, but to 
the designed function of the vehicle. 
Road-holding, steering and braking are 
especially vulnerable to incorrectly 
pressurised, badly fitted or worn tires.

Tires of the correct size and type, but of 
different make have widely varying 
characteristics. It is therefore 
recommended that only Jaguar approved 
tires are fitted to all wheels. 

!

WARNING:

Always ensure replacement tires have 
the correct rating and specifications 
(e.g. load index, size, speed rating) for 
your vehicle. Contact your Jaguar 
Dealer for more information.

!

WARNING:

When using tires other than those 
recommended by Jaguar, do not 
exceed the speed capacity 
recommended by the manufacturer.