2005 BUICK CENTURY wheel size

Tire Size
The following illustration shows an example of a typical
passenger vehicle tire size.
(A) P-Metric Tire:The United States version of a
metric tire sizing system. The letter P as the rst
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 percent 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 speed rating of the tire. The load
index represents the load carry capacity a tire is certied
to carry. The load index can range from 1 to 279.
The speed rating is the maximum speed a tire is certied
to carry a load. Speed ratings range from A to Z.
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{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. SeeCompact Spare
Tire on page 5-81.
{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.
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.
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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 a crash. If you have to replace a
wheel, use a new GM original equipment wheel.
Tire Chains
{CAUTION:
If your vehicle has P225/60R16 size tires, don’t
use tire chains, there’s not enough clearance.
Tire chains used on a vehicle without the
proper amount of clearance can cause damage
to the brakes, suspension or other vehicle
parts. The area damaged by the tire chains
could cause you to lose control of your vehicle
and you or others may be injured in a crash.
CAUTION: (Continued)
CAUTION: (Continued)
Use another type of traction device only if its
manufacturer recommends it for use on your
vehicle and tire size combination and road
conditions. Follow that manufacturer’s
instructions. To help avoid damage to your
vehicle, drive slowly, readjust or remove the
device if it’s contacting your vehicle, and don’t
spin your wheels.
If you do nd traction devices that will t,
install them on the front tires.
Notice:If your vehicle has a tire size other than
P225/60R16 size tires, use tire chains only where
legal and only when you must. Use only SAE Class
‘‘S’’ type chains that are the proper size for your
tires. Install them on the front tires and tighten them
as tightly as possible with the ends securely
fastened. Drive slowly and follow the chain
manufacturer’s instructions. If you can hear the
chains contacting your vehicle, stop and retighten
them. If the contact continues, slow down until
it stops. Driving too fast or spinning the wheels with
chains on will damage your vehicle.
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Storing a Flat or Spare Tire
and Tools
{CAUTION:
Storing a jack, a tire, or other equipment in the
passenger compartment of the vehicle could
cause injury. In a sudden stop or collision,
loose equipment could strike someone.
Store all these in the proper place.
After the compact spare tire is put on the vehicle, store
the at tire in the trunk. Use the following procedure
to secure the at tire in the trunk.When storing a full-size tire, use the extension with the
protector, located in the foam holder, to help avoid
wheel surface damage. To store a full-size tire, place
the tire valve stem facing down, and then remove
the protector and attach the retainer securely. Store the
cover as far forward as possible.
When storing a compact spare tire in the trunk, put the
protector/guide back in the foam holder.
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The compact spare is for temporary use only. Replace
the compact spare tire with a full-size tire as soon
as you can. SeeCompact Spare Tire on page 5-81.
See the storage instructions label to return the compact
spare to the trunk properly.
Be sure to calibrate low tire ination system after you
replace the compact spare tire with a full-sized tire.
SeeInation - Tire Pressure on page 5-60.A. Retainer
B. Cover
C. Compact Spare Tire
D. Nut
E. Jack
F. Wheel Wrench
G. Extension and Protector
H. Bolt Screw
I. Foam Holder
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Compact Spare Tire
Although the compact spare tire was fully inated when
the 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 the vehicle, check
to make sure it 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).
However, It is best to replace the compact spare with
a full-size tire as soon as possible. The spare will
last longer and be in good shape in case it is needed
again. The tire ination monitor system must be
reset after installing or removing the compact spare.
SeeTire Pressure Monitor System on page 5-61.Notice:When the compact spare is installed,
do not 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.
Do not use the compact spare on other vehicles.
Do not mix the compact spare tire or wheel with other
wheels or tires. They will not t. Keep the spare tire and
its wheel together.
Notice:Tire chains will not t your compact spare.
Using them can damage your vehicle and can
damage the chains too. Do not use tire chains on
your compact spare.
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