GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-17942154) - 2025
366 Vehicle Care
Treadwear
T
h
e treadwear grade is acomparative
rating based on the wear rate of the tire
when tested under controlled conditions
on aspecified government test course.
For example, a tire graded 150 would wear
one and one-half (1½) times as well on the
government course as atire 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. Atire marked Cmay have
poor traction performance. Warning:
The traction grade assigned to this
tire is based on straight-ahead braking
traction tests, and does not include
ac
celeration, cornering, hydroplaning, or
peak traction characteristics.
Temperature
The temperature grades are A(the
highest), 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 aspecified
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
Ccorresponds to alevel of performance
which all passenger car tires must meet
under the Federal Motor Safety Standard
No. 109. Grades Band Arepresent 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 atire that
is properly inflated and not overloaded.
Excessive speed, underinflation, or
excessive loading, either separately or in
co
mbination, can cause heat buildup and
possible tire failure.
Wheel Alignment and Tire
Balance
The tires and wheels were aligned and balanced
at the factory to provide the longest tire life
and best overall performance. Adjustments
to wheel alignment and tire balancing are
not necessary on aregular basis. Consider an
alignment check if there is unusual tire wear or
the vehicle is significantly pulling to one side or
the other. Some slight pull to the left or right,
depending on the slope of the road and/or
other road surface variations such as troughs or
ruts, is normal. If the vehicle is vibrating when
driving on asmooth road, the tires and wheels
may need to be rebalanced. See your dealer for
proper diagnosis.
Wheel Replacement
Replace any wheel that is bent, cracked, or
badly rusted or corroded. If wheel nuts keep
coming loose, the wheel, wheel bolts, and
wheel nuts should be replaced. If the wheel