Winter Driving
Here are some tips for winter driving:
Have your vehicle in good shape for winter.
You may want to put winter emergency supplies in
your vehicle.
Also seeTires on page 5-52.Include an ice scraper, a small brush or broom, a supply
of windshield washer uid, a rag, some winter outer
clothing, a small shovel, a ashlight, a red cloth, and a
couple of re ective warning triangles. And, if you will be
driving under severe conditions, include a small bag of
sand, a piece of old carpet, or a couple of burlap bags to
help provide traction. Be sure you properly secure these
items in your vehicle.
Driving on Snow or Ice
Most of the time, those places where the tires meet the
road probably have good traction.
However, if there is snow or ice between the tires and
the road, you can have a very slippery situation. You will
have a lot less traction, or grip, and will need to be very
careful.
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Uniform Tire Quality Grading
Quality 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
The following information relates to the system
developed by the United States National Highway Traffic
Safety Administration (NHTSA), which grades tires by
treadwear, traction, and temperature performance. This
applies only to vehicles sold in the United States. The
grades are molded on the sidewalls of most passenger
car tires. The Uniform Tire Quality Grading (UTQG)
system does not apply to deep tread, winter-type snow
tires, space-saver, or temporary use spare tires, tires with
nominal rim diameters of 10 to 12 inches (25 to 30 cm),
or to some limited-production tires.
While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a speci ed government test course. For
example, a tire graded 150 would wear one and a
half (1.5) 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 signi cantly from the norm
due to variations in driving habits, service practices,
and differences in road characteristics and climate.
Traction – AA, A, B, C
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 speci ed 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.
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