2004 CHEVROLET IMPALA tire pressure

Speed Rating:An alphanumeric code assigned to a
tire indicating the maximum speed at which a tire
can operate.
Traction:The friction between the tire and the road
surface. The amount of grip provided.
Tread:The portion of a tire that comes into contact
with the road.
Treadwear Indicators:Narrow bands, sometimes
called “wear bars,” that show across the tread of a tire
when only 2/32 inch of tread remains. SeeWhen It
Is Time for New Tires on page 5-76.
UTQGS:Uniform Tire Quality Grading Standards,
a tire information system that provides consumers with
ratings for a tire’s traction, temperature and treadwear.
Ratings are determined by tire manufacturers using
government testing procedures. The ratings are molded
into the sidewall of the tire. SeeUniform Tire Quality
Grading on page 5-77.Vehicle Capacity Weight:The number of designated
seating positions multiplied by 150 lbs. (68 kg) plus
the rated cargo load. SeeLoading Your Vehicle
on page 4-32.
Vehicle Maximum Load on the Tire:Load on an
individual tire due to curb weight, accessory weight,
occupant weight and cargo weight.
Vehicle Placard:A label permanently attached to a
vehicle showing the original equipment tire size
and recommended ination pressure. SeeLoading Your
Vehicle on page 4-32.
5-71

Ination - Tire Pressure
The tire and loading information label, shows the correct
ination pressures for your tires when they’re cold.
“Cold” means your vehicle has been sitting for at least
three hours or driven no more than 1 mile (1.6 km).
SeeLoading Your Vehicle on page 4-32, for the location
of your vehicle’s tire and loading information label.
Notice:Don’t let anyone tell you that underination
or overination is all right. It’s not. If your tires
don’t have enough air (underination), you can get
the following:
Too much exing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economy
If your tires have too much air (overination),
you can get the following:
Unusual wear
Bad handling
Rough ride
Needless damage from road hazards
When to Check
Check your tires once a month or more.
Don’t forget your compact spare tire. It should be at
60 psi (420 kPa).
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell if your tires are properly inated
simply by looking at them. Radial tires may look
properly inated even when they’re underinated.
Check the tire’s ination pressure when the tires
are cold. Cold means your vehicle has been sitting
for at least three hours or driven no more than
1 mile (1.6 km).
Remove the valve cap from the tire valve stem.
Press the tire gage rmly onto the valve to get a
pressure measurement. If the cold tire ination pressure
matches the recommended pressure on the Tire and
Loading Information label, no further adjustment is
necessary. If the ination pressure is low, add air until
you reach the recommended amount.
If you overll the tire, release air by pushing on the
metal stem in the center of the tire valve. Recheck the
tire pressure with the tire gage.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and moisture.
5-72

Tire Pressure Monitor System
If your vehicle has the tire pressure monitor system,
it can alert you to a large change in the pressure of one
tire. The system “learns” the pressure at each tire
throughout the operating speed range of your vehicle.
The system normally takes between 45 and 90 minutes
of driving to learn the tire pressures. This time may
be longer depending on your individual driving habits.
Learning need not be accumulated during a single
trip. Once learned, the system will remember the tire
pressures until the system is recalibrated.
After the system has learned tire pressures with
properly inated tires, the LOW TIRE PRESSURE
message will come on if the pressure in one tire
becomes 12 psi (83 kPa) lower than the other three
tires. The tire pressure monitor system won’t alert you
if the pressure in more than one tire is low, if the system
is not properly calibrated, or if the vehicle is moving
faster than 70 mph (110 km/h).The tire pressure monitor system detects differences in
tire rotation speeds that are caused by changes in
tire pressure. The system can alert you about a low
tire — but it doesn’t replace normal tire maintenance.
SeeTires on page 5-64.
When the LOW TIRE PRESSURE message comes on,
you should stop as soon as you can and check all
your tires for damage. (If a tire is at, seeIf a Tire Goes
Flat on page 5-81.) Also check the tire pressure in all
four tires as soon as you can. SeeInation - Tire
Pressure on page 5-72.
The LOW TIRE PRESSURE message will also be
displayed (while the ignition is on) until you reset
(calibrate) the system.
Don’t reset the tire pressure monitor system without rst
correcting the cause of the problem and checking
and adjusting the pressure in all four tires. If you reset
the system when the tire pressures are incorrect,
the system will not work properly and may not alert you
when a tire is low.
5-73

Any time you adjust a tire’s pressure, rotate your tires,
or have one or more tires repaired or replaced, you’ll
need to reset (calibrate) the tire pressure monitor
system. You’ll also need to reset the system whenever
you buy new tires and whenever the vehicle’s battery
has been disconnected.
To reset (calibrate) the system: The tire pressure
monitor system can be reset two ways. With the ignition
position at ON, pull the interior lamps control to the
ON and OFF settings three times.
It can also be reset through the radio using the
following steps:
1. Turn the ignition to ACC or ON and turn the
radio off.
2. Press and hold the TUNE DISP button on the radio
for at least ve seconds until SETTINGS is
displayed.
3. Press the SEEK SCAN up or down arrow to scroll
through the main menu.
4. Scroll until TIRE MON appears on the display.
5. Press the 1 PREV or 2 NEXT button to enter the
submenu. RESET will be displayed.6. Press the TUNE DISP button to reset. A chime will
be heard to verify the new setting and DONE will
be displayed for one second.
7. Once the monitor has been reset, scroll until EXIT
appears on the display.
8. Press the TUNE DISP button to exit programming.
A chime will be heard to verify exit.
The system completes the calibration process during
driving.
The system normally takes 15 to 20 minutes of driving
in each of three speed ranges to “learn” tire pressures.
The speed ranges are 15 to 40 mph (25 to 65 km/h),
40 to 65 mph (65 to 105 km/h) and above
65 mph (105 km/h). When learning is complete, the
system will alert you after two to eight minutes if a
tire is 12 psi (83 kPa) different from the other three tires.
Detection thresholds may be higher and detection
times may be longer on rough roads, curves and at high
speeds. The system is not capable of detection at
speeds greater than 70 mph (110 km/h).
5-74

Tire Inspection and Rotation
Tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km).
Any time you notice unusual wear, rotate your tires as
soon as possible and check wheel alignment. Also check
for damaged tires or wheels. SeeWhen It Is Time for
New Tires on page 5-76andWheel Replacement on
page 5-79for more information.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The rst rotation
is the most important. SeeScheduled Maintenance
on page 6-4for scheduled rotation intervals.
When rotating your tires, always use the correct rotation
pattern shown here.
Don’t include the compact spare tire in your tire rotation.After the tires have been rotated, adjust the front and
rear ination pressures as shown on the Tire and
Loading Information label.
Reset the Tire Ination Monitor System. SeeTire
Pressure Monitor System on page 5-73.
Make certain that all wheel nuts are properly tightened.
See “Wheel Nut Torque” underCapacities and
Specications on page 5-110.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the vehicle.
In an emergency, you can use a cloth or a
paper towel to do this; but be sure to use a
scraper or wire brush later, if you need to,
to get all the rust or dirt off. See “Changing a
Flat Tire” in the Index.
5-75

Compact Spare Tire
Although the compact spare tire was fully inated when
your vehicle was new, it can lose air after a time.
Check the ination pressure regularly. It should be
60 psi (420 kPa).
After installing the compact spare on your vehicle,
you should stop as soon as possible and make sure
your spare tire is correctly inated. The compact spare
is made to perform well at speeds up to 65 mph
(105 km/h) for distances up to 3,000 miles (5 000 km),
so you can nish your trip and have your full-size
tire repaired or replaced where you want. You must
calibrate the tire ination monitor system after installing
or removing the compact spare. SeeTire Pressure
Monitor System on page 5-73. The system may not work
correctly when the compact spare is installed on the
vehicle. Of course, it’s best to replace your spare with a
full-size tire as soon as you can. Your spare will last
longer and be in good shape in case you need it again.Notice:When the compact spare is installed, don’t
take your vehicle through an automatic car wash
with guide rails. The compact spare can get caught
on the rails. That can damage the tire and wheel,
and maybe other parts of your vehicle.
Don’t use your compact spare on other vehicles.
And don’t mix your compact spare tire or wheel with
other wheels or tires. They won’t t. Keep your spare tire
and its wheel together.
Notice:Tire chains won’t t your compact spare.
Using them can damage your vehicle and can
damage the chains too. Don’t use tire chains on
your compact spare.
5-93

Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. Reset oil life system. SeeEngine Oil on
page 5-18.An Emission Control Service.••
Visually check for any leaks or damage.See footnote (k).••
Inspect engine air cleaner lter. If necessary, replace lter. SeeEngine Air
Cleaner/Filter on page 5-25.An Emission Control Service. See footnote †.••
Rotate tires and check ination pressures and wear. SeeTires on page 5-64.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer uid levels and add uid as
needed.••
Perform any needed additional services. See “Additional Required Services” in
this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
Lubricate body components.See footnote (f).•
Check transaxle uid level and add uid as needed.•
Replace passenger compartment air lter (if equipped).See footnote (g).•
Inspect throttle system.See footnote (j).•
6-5

Owner Checks and Services
These owner checks and services should be performed
at the intervals specied to help ensure the safety,
dependability and emission control performance of your
vehicle. Your GM Goodwrench dealer can assist you
with these checks and services.
Be sure any necessary repairs are completed at once.
Whenever any uids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-12.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel ll.
Engine Oil Level Check
Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil on page 5-18for further
details.
Notice:It is important to check your oil regularly
and keep it at the proper level. Failure to keep your
engine oil at the proper level can cause damage
to your engine not covered by your warranty.
Engine Coolant Level Check
Check the engine coolant level and add
DEX-COOL®coolant mixture if necessary.
SeeEngine Coolant on page 5-29for further details.
Windshield Washer Fluid Level Check
Check the windshield washer uid level in the windshield
washer tank and add the proper uid if necessary.
At Least Once a Month
Tire Ination Check
Visually inspect your tires and make sure tires are
inated to the correct pressures. Do not forget to check
your spare tire. SeeTires on page 5-64for further
details.
Cassette Tape Player Service
Clean cassette tape player. Cleaning should be done
every 50 hours of tape play. SeeAudio System(s)
on page 3-56for further details.
6-9