Downloaded from www.Manualslib.com manuals search engine When replacing tires with those not having a TPC Spec. No., you should use
the same size,
load range, and constructiontype (bias, bias-bened, or radial)
as the original tires on your
vehicle . Although ~ is not generaly recommended ,
some alpha-size and metric-size tires can be interchanged. (For size
equivalency, contact your Chevrolet
dealer or a tire dealer) . A different size or
type of tire may affect ride,
handling, speedometer /odometer calibration,
vehicle ground clearance , and tire or tire chain clearance to the body or
chassis .
II replacing only a single tire, it should be paired on the same axle with the least worn tire of the other three.
UNIFORM TIRE QUALITY GRADING
The following information relates to the tire grading system developed by the
National Highway Traffic Safety' Adminlslration which will grade tires by
treadwear, traction and temperature performance.
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, the tire graded 150 would wear one and a haij (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 may depart significanlly from the norm due to variations in driving habits , service practices and. differences in road characteristics and climate.
TRACTION -A, B,C
. T~~tr~ction grades, from highest to lowest are: A, B, and C. They represent
the ' fiie'sability 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: Thetr.ction grade assigned to this tire is based on braking (straight-ahead) traction tests and· doellnot include cornerillg (turning) tractlon.
TEMPERATURE -A, B, C
The ·temperature grades are A (the highest), B, andC, representing the tire's
resistance to the generation of heat and its ability to dissipate heat when tested under controlled conditio 'ns 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 Federat 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.
Warning: The
temperature grade for Ihis tire is established for a tire that
is properly inflated and not overloaded. Excessive speed, underinllaiion, or excessive loading, either separately or in combination, can cause heat
buildup and possible lire failure.
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