2001 GMC ENVOY width

1-21
Q:What's wrong with this?
A:The belt is twisted across the body.
CAUTION:
You can be seriously injured by a twisted belt.
In a crash, you wouldn't have the full width
of the belt to spread impact forces. If a belt is
twisted, make it straight so it can work properly,
or ask your dealer to fix it.
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4-25 Driving Across an Incline
Sooner or later, an off-road trail will probably go across
the incline of a hill. If this happens, you have to decide
whether to try to drive across the incline. Here are some
things to consider:

A hill that can be driven straight up or down
may be too steep to drive across. When you go
straight up or down a hill, the length of the wheel
base (the distance from the front wheels to the
rear wheels) reduces the likelihood the vehicle will
tumble end over end. But when you drive across
an incline, the much more narrow track width
(the distance between the left and right wheels)
may not prevent the vehicle from tilting and rolling
over. Also, driving across an incline puts more
weight on the downhill wheels. This could cause
a downhill slide or a rollover.

Surface conditions can be a problem when you drive
across a hill. Loose gravel, muddy spots, or even wet
grass can cause your tires to slip sideways, downhill.
If the vehicle slips sideways, it can hit something
that will trip it (a rock, a rut, etc.) and roll over.
Hidden obstacles can make the steepness of the
incline even worse. If you drive across a rock with
the uphill wheels, or if the downhill wheels drop into
a rut or depression, your vehicle can tilt even more.
For reasons like these, you need to decide carefully
whether to try to drive across an incline. Just because
the trail goes across the incline doesn't mean you
have to drive it. The last vehicle to try it might have
rolled over.
CAUTION:
Driving across an incline that's too steep will
make your vehicle roll over. You could be seriously
injured or killed. If you have any doubt about
the steepness of the incline, don't drive across it.
Find another route instead.
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6-49 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, 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
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 specified government test course.
For example, a tire graded 150 would wear one and
a 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
-- 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 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.
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6-51
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted the
same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new GM original
equipment parts. This way, you will be sure to have the
right wheel, wheel bolts and wheel nuts for your vehicle.
CAUTION:
Using the wrong replacement wheels, wheel bolts
or wheel nuts on your vehicle can be dangerous.
It could affect the braking and handling of your
vehicle, make your tires lose air and make you lose
control. You could have a collision in which you or
others could be injured. Always use the correct
wheel, wheel bolts and wheel nuts for replacement.
NOTICE:
The wrong wheel can also cause problems with
bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper
height, vehicle ground clearance and tire or tire
chain clearance to the body and chassis.
See ªChanging a Flat Tireº in the Index for
more information.
Used Replacement Wheels
CAUTION:
Putting a used wheel on your vehicle is
dangerous. You can't know how it's been used or
how far it's been driven. It could fail suddenly
and cause an accident. If you have to replace a
wheel, use a new GM original equipment wheel.
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6-74 Vehicle Dimensions*
Wheelbase
2
-Door 100.5 inches (255.3 cm). . . . . . . . . . . . . . . .
4
-Door 107.0 inches (271.8 cm). . . . . . . . . . . . . . . .
Length
2WD 2
-Door 175.0 inches (444.5 cm). . . . . . . . . . .
2WD 4
-Door 175.4 inches (445.5 cm). . . . . . . . . . .
4
-Door 181.1 inches (460.0 cm). . . . . . . . . . . . . . . .
Height
2WD 2
-Door 66.0 inches (167.6 cm). . . . . . . . . . . .
4WD 2
-Door 66.9 inches (170.0 cm). . . . . . . . . . . .
2WD 4
-Door 65.9 inches (167.4 cm). . . . . . . . . . . .
4WD 4
-Door 67.0 inches (170.2 cm). . . . . . . . . . . . Width67.8 inches (172.2 cm) . . . . . . . . . . . . . . . . . . .
Front Tread
2WD 55.0 inches (139.6 cm). . . . . . . . . . . . . . . . . .
4WD 57.3 inches (145.4 cm). . . . . . . . . . . . . . . . . .
Rear Tread
2WD 54.7 inches (138.8 cm). . . . . . . . . . . . . . . . . .
4WD 55.1 inches (139.9 cm). . . . . . . . . . . . . . . . . .
*Figures reflect base equipment only.
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