2004 Oldsmobile Alero service

Don’t let the other end touch anything until the next
step. The other end of the negative (−) cabledoesn’t
go to the dead battery. It goes to a heavy, unpainted
metal engine part or to a remote negative (−)
terminal on the vehicle with the dead battery.9. Connect the other end of the negative (−) cable at
least 18 inches (45 cm) away from the dead battery,
but not near engine parts that move. The electrical
connection is just as good there, and the chance
of sparks getting back to the battery is much less.
10. Now start the vehicle with the good battery and run
the engine for a while.
11. Try to start the vehicle that has the dead battery. If
it won’t start after a few tries, it probably needs
service.
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Headlamp Aiming
Your vehicle has a headlamp system equipped with
horizontal and vertical aim indicators. The aim has been
pre-set at the factory and should need no further
adjustment. This is true even though your vertical and
horizontal aim indicators may not fall exactly on the
“0” (zero) marks on their scales.
If your vehicle is damaged in an accident, the headlamp
aim may be affected. Aim adjustment may be necessary
if it is difficult to see lane markers (for horizontal
aim), or if oncoming drivers flash their high beams at
you (for vertical aim). If you believe your headlamps
need to be re-aimed, we recommend that you take it to
your dealer for service; however, it is possible for
you to re-aim your headlamps as described in the
following procedure.Notice:To make sure your headlamps are aimed
properly, read all the instructions before beginning.
Failure to follow these instructions could cause
damage to headlamp parts.
To check the aim, the vehicle should be properly
prepared as follows:
•The vehicle must have all four tires on a perfectly
level surface.
•If necessary, pads may be used on an uneven
surface.
•The vehicle should not have any snow, ice or mud
attached to it.
•The vehicle should be fully assembled and all other
work stopped while headlamp aiming is being done.
•There should not be any cargo or loading of the
vehicle, except it should have a full tank of fuel and
one person or 160 lbs. (75 kg) on the driver’s seat.
•Close all doors.
•Tires should be properly inflated.
•Rock the vehicle to stabilize the suspension.
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Tires
Your new vehicle comes with high-quality tires made by
a leading tire manufacturer. If you ever have questions
about your tire warranty and where to obtain service,
see your GM Warranty booklet for details. For additional
information refer to the tire manufacturer’s booklet
included with your vehicle’s Owner’s Manual.
{CAUTION:
Poorly maintained and improperly used tires
are dangerous.
Overloading your tires can cause
overheating as a result of too much
friction. You could have an air-out and a
serious accident. See “Loading Your
Vehicle” in the Index.
CAUTION: (Continued)
CAUTION: (Continued)

Underinated tires pose the same danger
as overloaded tires. The resulting accident
could cause serious injury. Check all tires
frequently to maintain the recommended
pressure. Tire pressure should be checked
when your tires are cold.
Overinated tires are more likely to be
cut, punctured or broken by a sudden
impact — such as when you hit a pothole.
Keep tires at the recommended pressure.
Worn, old tires can cause accidents. If your
tread is badly worn, or if your tires have
been damaged, replace them.
Tire Sidewall Labeling
Useful information about a tire is molded into its
sidewall. The examples below show a typical passenger
car tire and a compact spare tire sidewall.
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(A) Tire Size:The tire size code is a combination of
letters and numbers used to define a particular
tire’s width, height, aspect ratio, construction type and
service description. See the “Tire Size” illustration
later in this section for more detail.
(B) Tire Performance Criteria Specication
(TPC Spec):Original equipment tires designed to GM’s
specific tire performance criteria have a TPC
specification code molded onto the sidewall. GM’s TPC
specifications meet or exceed all federal safety
guidelines.
(C) Department of Transportation (DOT):The
Department of Transportation (DOT) code indicates that
the tire is in compliance with the U.S. Department of
Transportation Motor Vehicle Safety Standards.
(D) Tire Identication Number (TIN):The letters and
numbers following DOT code are the Tire Identification
Number (TIN). The TIN shows the manufacturer
and plant code, tire size, and date the tire was
manufactured. The TIN is molded onto both sides of the
tire, although only one side may have the date of
manufacture.
Passenger Car Tire Example
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(A) Temporary Use Only:The compact spare tire or
temporary use tire has a tread life of approximately
3,000 miles (5 000 km) and should not be driven
at speeds over 65 mph (105 km/h). The compact spare
tire is for emergency use when a regular road tire
has lost air and gone flat. SeeCompact Spare Tire on
page 5-80andIf a Tire Goes Flat on page 5-70.
(B) Tire Ply Material:The type of cord and number of
plies in the sidewall and under the tread.
(C) Tire Identication Number (TIN):The Tire
Identification Number (TIN). The TIN shows the
manufacturer and plant code, tire size, and date the tire
was manufactured. The TIN is molded onto both
sides of the tire, although only one side may have the
date of manufacture.
(D) Maximum Cold Ination Load Limit:Maximum
load that can be carried and the maximum pressure
needed to support that load. SeeCompact Spare Tire
on page 5-80andLoading Your Vehicle on page 4-34.(E) Tire Ination:The temporary use tire or compact
spare tire should be inflated to 60 psi (420 kPa).
For more information on tire pressure and inflation see
Inflation - Tire Pressure on page 5-61.
(F) Tire Size:A combination of letters and numbers
define a tire’s width, height, aspect ratio, construction
type and service description. The letter “T” as the
first character in the tire size means the tire is for
temporary use only.
(G) Tire Performance Criteria Specication
(TPC Spec):Original equipment tires designed to GM’s
specific tire performance criteria have a TPC
specification code molded onto the sidewall. GM’s TPC
specifications meet or exceed all federal safety
guidelines.
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Tire Size
The following illustration shows an example of a typical
passenger car tire size.
(A) P-Metric Tire:The United States version of a
metric tire sizing system. The letter “P” as the
first character in the tire size means a passenger
vehicle tire engineered to standards set by the U. S.
Tire and Rim Association.(B) Tire Width:The three-digit number indicates the
tire section width in millimeters from sidewall to sidewall.
(C) Aspect Ratio:A two-digit number that indicates
the tire height-to-width measurements. For example, if
the tire size aspect ratio is “70,” as shown in item “C” of
the illustration, it would mean that the tire’s sidewall is
70% as high as it is wide.
(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire. The letter
“R” means radial ply construction; the letter “D” means
diagonal or bias ply construction; and the letter “B”
means belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel in inches.
(F) Service Description:These characters represent
the load range and the speed rating of a tire. The load
range represents the load carrying capacity a tire is
certified to carry. The load index can range from 1 to 279.
The speed rating is the maximum speed a tire is certified
to carry a load. Speed ratings range from “A” to “Z”.
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Buying New Tires
To find out what kind and size of tires you need, look at
the tire and loading information label. For an example
of this label and its location, seeLoading Your Vehicle
on page 4-34.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specification (TPC Spec)
number on each tire’s sidewall. When you get new tires,
get ones with that same TPC Spec number. That way
your vehicle will continue to have tires that are designed
to give proper endurance, handling, speed rating,
load range, traction, ride and other things during normal
service on your vehicle. If your tires have an all-season
tread design, the TPC number will be followed by
an “MS” (for mud and snow).
If you ever replace your tires with those not having a
TPC Spec number, make sure they are the same size,
load range, speed rating and construction type (bias,
bias-belted or radial) as your original tires.{CAUTION:
Mixing tires could cause 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 temporarily, it was developed
for use on your vehicle. See “Compact Spare
Tire” in the index.
{CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rim anges 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.
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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, 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
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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