2004 CADILLAC CTS tire pressure

Tire Terminology and Denitions
Air Pressure:The amount of air inside the tire pressing
outward on each square inch of the tire. Air pressure
is expressed in pounds per square inch (psi) or
kilopascal (kPa).
Accessory Weight:This means the combined weight
of optional accessories. Some examples of optional
accessories are, automatic transmission, power steering,
power brakes, power windows, power seats, and air
conditioning.
Aspect Ratio:The relationship of a tire’s height
to its width.
Belt:A rubber coated layer of cords that is located
between the plies and the tread. Cords may be made
from steel or other reinforcing materials.
Bead:The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
Bias Ply Tire:A pneumatic tire in which the plies are
laid at alternate angles less than 90 degrees to the
centerline of the tread.Cold Ination Pressure:The amount of air pressure
in a tire, measured in pounds per square inch (psi)
before a tire has built up heat from driving.
SeeInation - Tire Pressure on page 5-67.
Curb Weight:This means the weight of a motor
vehicle with standard and optional equipment including
the maximum capacity of fuel, oil and coolant, but
without passengers and cargo.
DOT Markings:A code molded into the sidewall of a
tire signifying that the tire is in compliance with the
U.S. Department of Transportation motor vehicle safety
standards. The DOT code includes the Tire Identication
Number (TIN), an alphanumeric designator which can
also identify the tire manufacturer, production plant,
brand and date of production.
GVWR:Gross Vehicle Weight Rating, seeLoading
Your Vehicle on page 4-34.
GAWR FRT:Gross Axle Weight Rating for the front
axle, seeLoading Your Vehicle on page 4-34.
GAWR RR:Gross Axle Weight Rating for the rear axle,
seeLoading Your Vehicle on page 4-34.
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Intended Outboard Sidewall:The side of an
asymmetrical tire that must always face outward when
mounted on a vehicle.
Kilopascal (kPa):The metric unit for air pressure.
There are 6.9 kPa’s to one psi.
Light Truck (LT-Metric) Tire:A tire used on light duty
trucks and some multipurpose passenger vehicles.
Load Index:An assigned number ranging from
1 to 279 that corresponds to the load carrying capacity
of a tire.
Maximum Ination Pressure:The maximum air
pressure to which a cold tire may be inated.
The maximum air pressure is molded onto the sidewall.
Maximum Load Rating:The load rating for a tire at
the maximum permissible ination pressure for that tire.
Maximum Loaded Vehicle Weight:The sum of
curb weight; accessory weight; vehicle capacity weight;
and production options weight.
Normal Occupant Weight:The number of occupants a
vehicle is designed to seat multiplied by 150 pounds
(68 kg). SeeLoading Your Vehicle on page 4-34.Occupant Distribution:Designated seating positions.
Outward Facing Sidewall:The side of a asymmetrical
tire that has a particular side that faces outward
when mounted on a vehicle. The side of the tire that
contains a whitewall, bears white lettering or bears
manufacturer, brand and or model name molding that is
higher or deeper than the same moldings on the
other sidewall of the tire.
Passenger (P-Metric) Tire:A tire used on
passenger cars and some light duty trucks and
multipurpose vehicles.
Recommended Ination Pressure:Vehicle
manufacturer’s recommended tire ination pressure and
shown on the tire placard. SeeInation - Tire Pressure
on page 5-67andLoading Your Vehicle on page 4-34.
Radial Ply tire:A pneumatic tire in which the ply cords
that extend to the beads are laid at 90 degrees to the
centerline of the tread.
Rim:A metal support for a tire and upon which the tire
beads are seated.
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Sidewall:The portion of a tire between the tread and
the bead.
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 5-73.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 5-75.
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 4-34.
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 4-34.
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Run-Flat Tires (CTS-V)
If your vehicle has run-at tires, there is no spare tire
and no tire changing equipment. Run-at tires perform
so well without any air that a Tire Pressure Monitor
(TPM) is used to alert you if a tire has lost pressure.
SeeTire Pressure Monitor System (CTS-V) on
page 5-70.
{CAUTION:
When the low tire warning light is displayed on
the instrument panel cluster, your vehicle’s
handling capabilities will be reduced during
severe maneuvers. If you drive too fast, you
could lose control of your vehicle. You or
others could be injured. Don’t drive over
55 mph (90 km/h) when the low tire warning
light is displayed. Drive cautiously and check
your tire pressures as soon as you can.If a tire goes at, you won’t need to stop on the side of
the road to change the tire. You can just keep on
driving. The tire can operate effectively with no air
pressure for up to 65 miles (105 km) at speeds up to
55 mph (90 km/h). The shorter the distance you
drive and the slower the speed, the greater the chance
that the tire will not have to be replaced. When a tire
is lled with air, it provides a cushion between the road
and the wheel. Because you won’t have this cushion
when driving on a deated run-at tire, try to avoid
potholes that could damage your wheel and require
replacement of it.
Some road hazards can damage a tire beyond repair.
This damage could occur even before you’ve driven
on the tire in a deated condition. When a tire has been
damaged, or if you’ve driven any distance on a
run-at tire, check with an authorized run-at tire service
center to determine whether the tire can be repaired
or should be replaced. To maintain your vehicle’s run-at
feature, all replacement tires must be self-supporting
tires. As soon as possible, contact the nearest
authorized GM or run-at servicing facility for inspection
and repair or replacement. To locate the nearest GM
or run-at servicing facility, call Roadside Service.
SeeRoadside Service on page 7-6for details.
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{CAUTION:
Run-at tires are constructed differently than
other tires and could explode during improper
service. You or others could be injured or
killed if you attempt to repair, replace,
dismount, or mount a run-at tire. Let only an
authorized run-at service center repair,
replace, dismount and mount run-at tires.
The valve stems on your run-at tires have sensors that
are part of the Tire Pressure Monitor System (TPMS).
These sensors contain batteries which are designed
to last for 10 years under normal driving conditions.
See your dealer if you ever need to have a wheel
replaced, or if the sensors ever need replacement.
Notice:Using liquid sealants can damage the tire
valves and tire pressure monitor sensors in your
run-at tires. This damage would not be covered
by warranty. Don’t use liquid sealants in your
run-at tires.
Ination - Tire Pressure
Tires need the correct amount of air pressure to
operate effectively.
Notice:Do not let anyone tell you that
under-ination or over-ination is all right. It is not.
If your tires do not have enough air (under-ination),
you can get the following:
Too much exing
Too much heat
Tire overloading
Premature or irregular wear
Poor handling
Reduced fuel economy
If your tires have too much air (over-ination),
you can get the following:
Unusual wear
Poor handling
Rough ride
Needless damage from road hazards
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A Tire and Loading Information label is attached to the
vehicle’s center pillar, below the driver’s door latch
or on the rear edge of the driver’s side, rear passenger
door. This label lists your vehicle’s original equipment
tires and their recommended cold tire ination pressures.
The recommended cold tire ination pressure, shown
on the label, is the minimum amount of air pressure
needed to support your vehicle’s maximum load
carrying capacity.
For additional information regarding how much weight
your vehicle can carry, and an example of the tire
and loading information label, seeLoading Your Vehicle
on page 4-34. How you load your vehicle affects
vehicle handling and ride comfort, never load your
vehicle with more weight than it was designed to carry.
When to Check
Check your tires once a month or more. Do not forget to
check the compact spare tire. If your vehicle has one,
it should be at 60 psi (420 kPa). For additional
information regarding the compact spare tire,
seeCompact Spare Tire on page 5-91.
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.
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High Speed Operation (CTS-V)
{CAUTION:
Driving at high speeds, 100 mph (160 km/h) or
higher, puts an additional strain on tires.
Sustained high-speed driving, causes
excessive heat build up and can cause sudden
tire failure. You could have a crash and you or
others could be killed. Some high-speed rated
tires require ination pressure adjustment for
high speed operation. When speed limits and
road conditions are such, that a vehicle can be
driven at high speeds, make sure the tires are
rated for high speed operation, in excellent
condition and set to the correct cold tire
ination pressure for the vehicle load.
The CTS-Vperformance series has 245/45R18 96W size
tires. These high-performance tires require ination
pressure adjustment when driving your vehicle at speeds
of 130 mph (209 km/h) or higher with occupants and
cargo weighing 600 lbs. (272 kg) up to 882 lbs. (400 kg).Use the following chart to determine the cold tire
ination pressure when operating your vehicle under
these conditions.
Tire Size: 245/45R18 96W Recommended Cold Tire
Ination Pressure for High Speed Operation at
130 mph (209 km/h) or more:
Occupant and
Cargo Weight:
Less than
600 lbs (272 kg)Occupant and
Cargo Weight:
600 lbs (272 kg)
Up to 882 lbs (400 kg)
(Vehicle Capacity
Weight)
Front Tires Rear Tires Front Tires Rear Tires
30 psi
(210 kPa)30 psi
(210 kPa)32 psi
(220 kPa)34 psi
(235 kPa)
When you end high-speed driving, return the tires to the
cold ination pressures shown on the tire and loading
information label. SeeLoading Your Vehicle on
page 4-34.
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Tire Pressure Monitor
System (CTS-V)
The Tire Pressure Monitor (TPM) System uses radio
and sensor technology to check tire pressure levels.
If your vehicle has this feature, sensors are mounted on
each run-at tire and wheel assembly. The TPM
sensors transmit tire pressure readings to a receiver
located in the vehicle. Using the Message Center,
tire pressure levels can be viewed by the driver.
For additional information about the message center
operation and displays, seeMessage Center (CTS-V)
on page 3-53.
When a low tire pressure condition is detected, a low
tire warning light, on the instrument panel cluster,
comes on to warn the driver.When the tire pressure
monitoring system warning
light is lit, one or more
of your tires is signicantly
under-inated.
You should stop and check your tires as soon as
possible, and inate them to the proper pressure as
indicated on the vehicle’s tire information placard.
Driving on a signicantly under-inated tire causes
the tire to overheat and can lead to tire failure.
Under-ination also reduces fuel efficiency and tire tread
life, and may affect the vehicle’s handling and stopping
ability. Each tire, should be checked monthly when
cold and set to the recommended ination pressure as
specied in the vehicle placard and owner’s manual.
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