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4 E V O p e r a t o r ’ s M a n u a l
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Contact Westward Industries for Manuals and Documentation. Do not copy.
5.5 Tires
5.5.1 Tire Choice
WARNING:
When replacing tires, it is recommended to use tires of the same size, speed rating, load
range and radial construction as originally installed on the vehicle. Use of any other tire specification may
seriously affect ride, handling, speedometer/odometer calibration, vehicle ground clearance, and tire
clearance to the body and chassis. Refer to VIN sticker for tire size and proper inflation pressure.
Uniform Tire Quality Grading
The uniform tire quality grading (UTQG) ratings of tires should be taken into account when selecting tires.
Westward Industries strongly recommends that any replacement tires have UTQG ratings equal to or
better than the original tires supplied with the vehicle.
Grades can be found where applicable on the tire sidewall between tread shoulder and maximum section
width. For example:
Treadwear 200 Traction AA Temperature A
DOT Quality Grades:
TREADWEAR: Numerical Value
TRACTION: AA, A, B, C
TEMPERATURE: A, B, C
All Passenger Car Tires Must Conform to Federal Safety Requirements in Addition to These Grades
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 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 highest to lowest, are AA, A, B, and C. Those 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.
