2005 GMC SIERRA DENALI wheel size

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. SeeLoading Your
Vehicle on page 4-42.
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. SeeInflation - Tire
Pressure on page 5-62.
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.
20-Inch Tires
If your vehicle has the optional 20-inch P275/55R20
size tires, they are classied as touring tires and
are designed for on road use. The low-prole, wide
tread design is not recommended for “off-road” driving.
SeeOperating Your All-Wheel-Drive Vehicle Off
Paved Roads on page 4-13, for additional information.
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(G) Single Tire Maximum Load:Maximum load that
can be carried and the maximum pressure needed to
support that load when used as a single. For information
on recommended tire pressure seeInation - Tire
Pressure on page 5-62andLoading Your Vehicle on
page 4-42.
Tire Size
The following examples show the different parts of a
tire size.(A) Passenger (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.
(A) Light Truck (LT-Metric) Tire:The United States
version of a metric tire sizing system. The letters LT as
the rst two characters in the tire size means a light truck
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 75, as shown in item C of the light
truck (LT-Metric) tire illustration, it would mean that the
tire’s sidewall is 75% 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:The service description
indicates the load range and speed rating of a tire. The
load index can range from 1 to 279. Speed ratings range
fromAtoZ. Passenger (P-Metric) Tire
Light Truck (LT-Metric) Tire
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Buying New Tires
To nd out what kind and size of tires you need, look at
the Certication/Tire label. SeeLoading Your Vehicle
on page 4-42, for more information about this
Certication/Tire label and where it can be found on
your vehicle.
The tires installed on your vehicle when it was new had a
Tire Performance Criteria Specications (TPC Spec)
number on each tire’s sidewall. When you get new tires,
GM recommends that you get tires 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).
Whenever you 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.
Your vehicle may be equipped with a different
size spare than the road tires (those originally
installed on your vehicle). When new, your
vehicle included a spare tire and wheel
assembly with a similar overall diameter as
your vehicle’s road tires and wheels, so it is all
right to drive on it. Because this spare was
developed for use on your vehicle, it will not
affect vehicle handling.
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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:
Do not use tire chains. There is 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. 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, re-adjust or remove the
device if it is contacting your vehicle, and do
not spin your wheels. If you do nd traction
devices that will t, install them on the
rear tires.
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7. Make sure the tire is stored securely. Push, pull, (A)
and then try to turn (B) the tire. If the tire moves,
use the wheel wrench to tighten the cable.
8. Reinstall the spare tire lock (if equipped).
Spare Tire
Your vehicle, when new, had a fully-inated spare tire.
A spare tire may lose air over time, so check its
ination pressure regularly. SeeInation - Tire Pressure
on page 5-62andLoading Your Vehicle on page 4-42
for information regarding proper tire ination and loading
your vehicle. For instruction on how to remove, install
or store a spare tire, seeRemoving the Flat Tire
and Installing the Spare Tire on page 5-76andStoring
a Flat or Spare Tire and Tools on page 5-87.
After installing the spare tire on your vehicle, you should
stop as soon as possible and make sure the spare is
correctly inated. Have the damaged or at road
tire repaired or replaced as soon as you can and
installed back onto your vehicle. This way, a spare tire
will be available in case you need it again.
Your vehicle may have a different size spare tire than
the road tires, those originally installed on your vehicle.
This spare tire was developed for use on your vehicle,
so it is all right to drive on it.
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