SERVICING AND MAINTENANCE
305
T
IRE
R
OTATION
R
ECOMMENDATIONS
The tires on the front and rear of your vehicle
operate at different loads and perform different
steering, handling, and braking functions. For
these reasons, they wear at unequal rates.
These effects can be reduced by timely rotation
of tires. The benefits of rotation are especially
worthwhile with aggressive tread designs such
as those on On/Off Road type tires. Rotation will
increase tread life, help to maintain mud, snow,
and wet traction levels, and contribute to a
smooth, quiet ride.
For the proper maintenance intervals
page 254. The reasons for any rapid or
unusual wear should be corrected prior to
rotation being performed.
The suggested rotation method is the “forward
cross” shown in the following diagram. This
rotation pattern does not apply to some
directional tires that must not be reversed.
Tire Rotation (Forward Cross)
DEPARTMENT OF TRANSPORTATION
UNIFORM TIRE QUALITY GRADES
The following tire grading categories
were established by the National
Highway Traffic Safety Administration.
The specific grade rating assigned by the
tire's manufacturer in each category is
shown on the sidewall of the tires on
your vehicle.
All passenger vehicle tires must conform
to Federal safety requirements in
addition to these grades.
T
READWEAR
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 times as well on
the government course as a tire graded
100. The relative performance of tires
depends upon the actual conditions of
Observe the traction device manufacturer’s
instructions on the method of installation,
operating speed, and conditions for use.
Always use the suggested operating speed
of the device manufacturer’s if it is less
than 30 mph (48 km/h).
Do not use traction devices on a compact
spare tire.
CAUTION!
(Continued)
CAUTION!
Proper operation of four-wheel drive vehicles
depends on tires of equal size, type and
circumference on each wheel. Any difference
in tire size can cause damage to the power
transfer unit. Tire rotation schedule should be
followed to balance tire wear.
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