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CAUTION!
After inspecting or adjusting the tire pressure, al-
ways reinstall the valve stem cap–if equipped. This
will prevent moisture and dirt from entering the
valve stem, which could damage the valve stem.
Inflation pressures specified on the placard are always
“cold tire inflation pressure”. Cold tire inflation pressure
is defined as the tire pressure after the vehicle has not
been driven for at least 3 hours, or driven less than 1mile
(1 km) after a 3 hour period. The cold tire inflation
pressure must not exceed the maximum inflation pres-
sure molded into the tire side wall.
Check tire pressures more often if subject to a wide range
of outdoor temperatures, as tire pressures vary with
temperature changes.Tire pressures change by approximately 1 psi (7 kPa) per
12° F (7° C) of air temperature change. Keep this in mind
when checking tire pressure inside a garage, especially in
the winter.
Example: If garage temperature = 68° F (20° C) and the
outside temperature = 32° F (0° C) then the cold tire
inflation pressure should be increased by 3 psi (21 kPa),
which equals 1 psi (7 kPa) for every 12° F (7° C) for this
outside temperature condition.
Tire pressure may increase from 2 to 6 psi (13 to 40 kPa)
during operation. DO NOT reduce this normal pressure
build up or your tire pressure will be too low.
Tire Pressures for High Speed Operation
The manufacturer advocates driving at safe speeds
within posted speed limits. Where speed limits or condi-
tions are such that the vehicle can be driven at high
speeds, maintaining correct tire inflation pressure is very
important. Increased tire pressure and reduced vehicle
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loading may be required for high speed vehicle opera-
tion. Refer to original equipment or an authorized tire
dealer for recommended safe operating speeds, loading
and cold tire inflation pressures.
WARNING!
High speed driving with your vehicle under maxi-
mum load is dangerous. The added strain on your
tires could cause them to fail. You could have a
serious accident. Don’t drive a vehicle loaded to the
maximum capacity at continuous speeds above 75
mph (120 km/h).
Radial-Ply Tires
WARNING!
Combining radial ply tires with other types of tires
on your vehicle will cause your vehicle to handle
poorly. The instability could cause an accident. Al-
ways use radial ply tires in sets of four (or 6, in case
of trucks with dual rear wheels). Never combine
them with other types of tires.
Cuts and punctures in radial tires are repairable only in
the tread area because of sidewall flexing. Consult your
authorized tire dealer for radial tire repairs.
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Limited Use Spare — If Equipped
The limited use spare tire is for temporary emergency use
on your vehicle. This tire is identified by a limited use
spare tire warning label located on the limited use spare
tire and wheel assembly. This tire may look like the
original equipped tire on the front or rear axle of your
vehicle, but it is not. Installation of this limited use spare
tire affects vehicle handling. Since it is not the same tire,
replace (or repair) the original tire and reinstall on the
vehicle at the first opportunity.WARNING!
The limited use spare tires are for emergency use
only. Installation of this limited use spare tire affects
vehicle handling. With this tire, do not drive more
than 60 mph (100 km/h). Keep inflated to the cold
tire inflation pressure listed on either your tire
placard or limited use spare tire and wheel assembly.
Replace (or repair) the original tire at the first
opportunity and reinstall it on your vehicle. Failure
to do so could result in loss of vehicle control.
Tire Spinning
When stuck in mud, sand, snow, or ice conditions, do not
spin your vehicle’s wheels above 35 mph (55 km/h).
See the paragraph on Freeing A Stuck Vehicle in Section
6 of this manual.
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Life of Tire
The service life of a tire is dependent upon varying
factors including but not limited to:
•Driving style
•Tire pressure
•Distance driven
WARNING!
Tires and spare tire should be replaced after six
years, regardless of the remaining tread. Failure to
follow this warning can result in sudden tire failure.
You could lose control and have an accident result-
ing in serious injury or death.
Keep unmounted tires in a cool, dry place with as little
exposure to light as possible. Protect tires from contact
with oil, grease and gasoline.
Replacement Tires
The tires on your new vehicle provide a balance of many
characteristics. They should be inspected regularly for
wear and correct cold tire inflation pressure. The manu-
facturer strongly recommends that you use tires equiva-
lent to the originals in size, quality and performance
when replacement is needed (see the paragraph on tread
wear indicators). Refer to the Tire and Loading Informa-
tion placard for the size designation of your tire. The
service description and load identification will be found
on the original equipment tire. Failure to use equivalent
replacement tires may adversely affect the safety, han-
dling, and ride of your vehicle. We recommend that you
contact your original equipment or an authorized tire
dealer with any questions you may have on tire specifi-
cations or capability.
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Improper alignment will not cause vehicle vibration.
Vibration may be a result of tire and wheel out-of-
balance. Proper balancing will reduce vibration and
avoid tire cupping and spotty wear.
SUPPLEMENTAL TIRE PRESSURE INFORMATION
A light load vehicle condition is defined as two passen-
gers {150 lbs (68 kg) each} plus 200 lbs (91kg) of cargo.
Cold tire inflation pressures for a lightly loaded vehicle
will be found on the face of the driver’s door.
TIRE CHAINS
Use “Class U” chains on Power Wagon models, or other
traction aids that meet SAE Type “U” specifications.
NOTE:Chains must be the proper size for the vehicle,
as recommended by the chain manufacturer.
CAUTION!
To avoid damage to your vehicle, tires or chains, observe the
following precautions:
•Because of limited chain clearance between tires and other
suspension components, it is important that only chains in
good condition are used. Broken chains can cause serious
vehicle damage. Stop the vehicle immediately if noise
occurs that could suggest chain breakage. Remove the
damaged parts of the chain before further use.
•Install chains as tightly as possible and then retighten after
driving about 1/2 mile (0.8 km).
•Do not exceed 45 mph (72 km/h).
•Drive cautiously and avoid severe turns and large bumps,
especially with a loaded vehicle.
•Do not install tire chains on front wheels of 4x2 vehicles.
•Do not drive for a prolonged period on dry pavement.
•Observe the tire chain manufacturer’s instructions on
method of installation, operating speed, and conditions for
usage. Always use the lower suggested operating speed of
the chain manufacturer if different than the speed recom-
mended by the manufacturer.
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These cautions apply to all chain traction devices, includ-
ing link and cable (radial) chains.
NOTE:On 4x4 Power Wagon models, class “U” snow
chains are permitted on the rear wheels only of vehicles
equipped with LT285/70R17D.
CAUTION!
Do not use tire chains on the 4X4 front wheels of
Ram Trucks equipped with LT285/70R17D. There
may not be adequate clearance for the chains and
you are risking structural or body damage to your
vehicle.
SNOW TIRES
Snow tires should be of the same size and type construc-
tion as the front tires. Consult the manufacturer of the
snow tire to determine any maximum vehicle speed
requirement associated with the tire. These tires should
always be operated at the vehicle maximum capacity
inflation pressures under any load condition.
While studded tires improve performance on ice, skid
and traction capability on wet or dry surfaces may be
poorer than that of non-studded tires. Some states pro-
hibit studded tires; therefore, local laws should be
checked before using these tire types.
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rear axle systems (GAWR). Total load must be limited so
GVWR and front and rear GAWR are not exceeded.
Payload
The payload of a vehicle is defined as the allowable load
weight a truck can carry, including the weight of the
driver, all passengers, options and cargo.
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum permissible load on the front
and rear axles. The load must be distributed in the cargo
area so that the GAWR of each axle is not exceeded.
Each axle GAWR is determined by the components in the
system with the lowest load carrying capacity (axle,
springs, tires or wheels). Heavier axles or suspension
components sometimes specified by purchasers for in-
creased durability does not necessarily increase the vehi-
cle’s GVWR.
Tire Size
The tire size on the Label represents the actual tire size on
your vehicle. Replacement tires must be equal to the load
capacity of this tire size.
Rim Size
This is the rim size that is appropriate for the tire size
listed.
Inflation Pressure
This is the cold tire inflation pressure for your vehicle for
all loading conditions up to full GAWR.
Curb Weight
The curb weight of a vehicle is defined as the total weight
of the vehicle with all fluids, including vehicle fuel, at full
capacity conditions, and with no occupants or cargo
loaded into the vehicle. The front and rear curb weight
values are determined by weighing your vehicle on a
commercial scale before any occupants or cargo are
added.
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•Total weight must be distributed between the tow
vehicle and the trailer such that the following four
ratings are not exceeded:
1. GVWR
2. GTW
3. GAWR
4. Tongue weight rating for the trailer hitch utilized
(This requirement may limit the ability to always
achieve the 10% to 15% range of tongue weight as a
percentage of total trailer weight).
Towing Requirements — Tires
Do not attempt to tow a trailer while using a compact
spare tire.
Proper tire inflation pressures are essential to the safe
and satisfactory operation of your vehicle. Refer to the
Tires–General Information section of this manual on
Tire Pressures for proper tire inflation procedures.
Also, check the trailer tires for proper tire inflation
pressures before trailer usage.
Check for signs of tire wear or visible tire damage
before towing a trailer. Refer to the Tires–General
Information section of this manual on Tread Wear
Indicators for the proper inspection procedure.
When replacing tires refer to the Tires–General Infor-
mation section of this manual on Replacement Tires for
proper tire replacement procedures. Replacing tires
with a higher load carrying capacity will not increase
the vehicle’s GVWR and GAWR limits.
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