________________________________________________ T_i_re_ s_a_ n_d_ w_ h_e_e_l_s __ _
Uniform tire quality grading
• Tread wea r
• Tract ion AA A B C
• Tempera tur e A B C
Quality g rades ca n be fou nd where ap plica ble on t he tire side wa ll
between tread shou lde r and max imum section widt h =>
page 295,
fig. 2 10 .
For example: Tread wear 200 , Tract ion AA, Temp e rat ure A.
All passenger car tires must conform to Federa l Safety Requirements
in addi t ion to t hese g rades.
Tread wear
The tread wear grade is a comp ar ative rati ng based o n the wear rat e
of the tire when teste d un der cont rolled conditions on a specifie d
governme nt test course.
For examp le, a tire graded
150 would wear one and one half (1 1/2)
times as well o n t he governmen t course as a t ire graded 10 0 .
The relat ive performa nce of tires de pends upon t he act ual cond it io ns
of their use, however, an d may de pa rt sig nificantly from t he norm
due to var iat io ns in d riving ha bits, se rvice prac t ices and differences in
road characterist ics and climate .
Traction
The traction gra d es, from highes t to lowest, are AA, A, Band C. Those
grades represent the t ire's ab ility to st op o n wet pavem en t as
measu red under contro lled condit ions on specified government test
surfaces of asphal t and conc ret e . A ti re marked C may have poo r t rac-
tion performance =>& .
Temperature
The temperature gr ades are A (t he highest), B, a nd C, rep resenting
t he t ire's resistanc e to t he generat ion of heat and its ab ility to dissi-
pate heat when teste d un der contro lled conditions on a specifie d
indoor laboratory t est wh eel.
Safety first
Sustai ned high temperat ure can cause the material of the tire to
degener at e and redu ce tir e life, and exces sive t em perat ure ca n lead
to sudde n tire fa ilure=> & .
The grade C corresponds to a leve l of perfo rmance which a ll
passenger ca r tires must meet un der t he Federal Mot or Vehicle
Safety Stan da rd No. 109. Grades Band A represent higher levels of
perfor man ce on t he laborat ory tes t wheel t han t he minimu m
req uired by law.
& 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.
& WARNING
The temperature grade for this tire is established for a tire that is
properly inflated and not overloaded . Excessive speed, underinfla-
tion , or excessive loading , either separately or in combination, can
cause heat buildup and possible tire failure. •
Winter tires
Winter tires can improve vehicle handling on snow and
ice. At temper atures below 45 °F (7 °C) we recom m end
changing to winter tires.
In some heavy snow areas, loca l gover nments may require true
winte r or "snow" t ires, th os e wit h very dee ply cut t read . These tire s
should only be used in pairs and be installed on all four wheels . Make
sure you purchase snow t ires t ha t are the same size and constr uction
type as the other t ires on your ve hicle .
Your vehicle is equi pp ed with a ll-wheel d rive, this will improve trac-
t ion dur ing wint e r dr iving, even wit h t he standar d t ires. However, we
st rongly recommend that you a lways eq uip a ll four wheels on you r .,_
Vehicle care Technical data
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