winter tires BUICK TERRAZA 2007 Owner's Manual

Stay in your own lane when driving on two-lane
roads in hills or mountains. Do not swing wide
or cut across the center of the road. Drive at
speeds that let you stay in your own lane.
As you go over the top of a hill, be alert. There
could be something in your lane, like a stalled
car or an accident.
You may see highway signs on mountains that
warn of special problems. Examples are long
grades, passing or no-passing zones, a falling
rocks area, or winding roads. Be alert to these
and take appropriate action.
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 449.
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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 reective 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.What is the worst time for this? Wet ice. Very cold
snow or ice can be slick and hard to drive on.
But wet ice can be even more trouble because it
may offer the least traction of all. You can get
wet ice when it is about freezing, 32°F (0°C), and
freezing rain begins to fall. Try to avoid driving
on wet ice until salt and sand crews can get there.
Whatever the condition — smooth ice, packed,
blowing, or loose snow — drive with caution.
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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 specied
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 signicantly 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 specied
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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