Treadwear; Traction; Temperature; Snow Chains - Volvo S40 2005 Owner's Manual

2005 Volvo S40

TREADWEAR

The treadwear 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 one half (1 1/2) 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 many depart
significantly from the norm due to variation in driving habits, maintenance practices and differences in
road characteristics and climate.

TRACTION

The traction grades, from highest to lowest, are AA, A, B, and C, as measured under controlled
conditions on specified government test surfaces of asphalt and concrete. A tire marked C may have
poor traction performance. The traction grade assigned to this tire is based on braking (straight-ahead)
traction tests and is not a measure of cornering (turning) traction.
WARNING!
The traction grade assigned to this tire is based on braking (straight-ahead) traction tests and is not a
measure of cornering (turning) traction.

TEMPERATURE

The temperature grades are AA (the highest), A, 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 minimum level of performance that all passenger vehicle tires must meet under the Federal Motor
Safety Standard No. 109. Grades B and A represent higher levels of performance on the laboratory test
wheel than the minimum required by law.
WARNING!
The temperature grade for this tire 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 buildup and tire failure.
pg. 132 Snow chains, snow tire, studded tires

Snow chains

Snow chains can be used on your Volvo with the following restrictions:
Snow chains should be installed on front wheels only. Use only Volvo approved snow chains.
If accessory, aftermarket or "custom" tires and wheels are installed and are of a size different than the
original tires and wheels, chains in some cases CANNOT be used. Sufficient clearances between chains
http://new.volvocars.com/ownersdocs/2005/2005_S40/05s40_08a.htm (11 of 17)8/12/07 12:18 AM