2003 PONTIAC BONNEVILLE width

Q: What’s wrong with this?
I I I I I J
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.
4-17

Headlamp Horizontal Aiming
Turn the horizontal aiming screw (A) until the
indicator
(B) is lined up with zero.
B
A
Once the horizontal aim is adjusted, then adjust the
vertical aim.
Headlamp Vertical Aiming
Notice: Horizontal aiming must be performed
before making any adjustments to the vertical aim.
Adjusting the vertical aim first will result in an incorrect headlamp aim.
1. Find the aim dot on the lens of the low
beam lamps.
2. Measure the distance from the ground to the aim
dot on each lamp;
if left low beam, subtract two
inches. Record this distance.
3. At the wall or other flat surface, measure from the
ground upward the recorded distance from Step
2
and draw or tape a horizontal line the width of
the vehicle.
5-54

Mixing tires couh :ause you to lose control
while driving. If you mix tires of different sizes
or types (radial and bias-belted tires), the
vehicle may not handle properly, and you
could have a crash. Using tires of different
sizes may also cause damage to your vehicle.
Be sure to use the same size and type tires on
all wheels. It’s all right to drive with your
compact spare, though.
It was developed for
use on your vehicle.
I
If you use bias-ply tires on your vehicle, the
wheel rim flanges could develop cracks after many miles of driving.
A tire and/or wheel
could fail suddenly, causing a crash. Use only
radial-ply tires with the wheels on your vehicle.
5-68
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 (1.5) times as well on the government course as

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.
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
Changing a Flat Tire on page 5-73 for more
information.
Used Replacement Wheels
Using the wrong replacement wheels, wheel
bolts or wheel nuts on your vehicle can be
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.
~ dangerous. It could affect the braking and Putting a us
wheel o ~OL licle is
dangerous. You can’t know how it’s been used
or how far it’s been driven.
It could fail
suddenly and cause a crash. If you have to
replace a wheel, use a new GM original
equipment wheel.
I
5-70