2007 RAM CHASSIS CAB Owners Manual

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WARNING!Overloading of your tires is dangerous. Overloading
can cause tire failure, affect vehicle handling, and
increase your stopping distance. Use tires of the
recommended load capacity for your vehicle. Never
overload them.
TIRES — GENERAL INFORMATION
Tire Pressure
Proper tire inflation pressure is essential to the safe and
satisfactory operation of your vehicle. Three primary
areas are affected by improper tire pressure: 1. Safety—
WARNING!• Improperly inflated tires are dangerous and can
cause accidents.
• Under inflation increases tire flexing and can
result in tire failure.
• Over inflation reduces a tire’s ability to cushion
shock. Objects on the road and chuckholes can cause
damage that result in tire failure.
• Unequal tire pressures can cause steering prob-
lems. You could lose control of your vehicle.
• Over inflated or under inflated tires can affect
vehicle handling and can fail suddenly, resulting in
loss of vehicle control.
• Unequal tire pressures from one side of the vehicle
to the other can cause the vehicle to drift to the right
or left.
• Always drive with each tire inflated to the recom-
mended cold tire inflation pressure.314 STARTING AND OPERATING

2. Economy—
Improper inflation pressures can cause uneven wear
patterns to develop across the tire tread. These abnormal
wear patterns will reduce tread life resulting in a need for
earlier tire replacement. Under inflation, also increases
tire rolling resistance and results in higher fuel consump-
tion.
3. Ride Comfort and Vehicle Stability—
Proper tire inflation contributes to a comfortable ride.
Over inflation produces a jarring and uncomfortable ride.
Tire Inflation Pressures
The proper cold tire inflation pressure is listed either on
the face of the driver’s door or on the driver’s side “B”
pillar.
Some vehicles may have Supplemental Tire Pressure
Information for vehicle loads that are less than the maximum loaded vehicle condition. These pressure con-
ditions will be found in the “Supplemental Tire Pressure
Information” section of this manual.
The pressure should be checked and adjusted as well as
inspecting for signs of tire wear or visible damage at least
once a month. Use a good quality pocket-type gauge to Tire Placard Location STARTING AND OPERATING 315
5

check tire pressure. Do not make a visual judgement
when determining proper inflation. Radial tires may look
properly inflated even when they are under inflated.
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 1 mile
(1 km) after a 3 hour period. The cold tire inflation
pressure must not exceed the maximum inflation pres-
sure molded into the tire sidewall. 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.316 STARTING AND OPERATING

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
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. STARTING AND OPERATING 317
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Compact Spare Tire — If Equipped
The compact spare is for temporary emergency use with
radial tires. It is engineered to be used on your style
vehicle only. Since this tire has limited tread life, the
original tire should be repaired (or replaced) and rein-
stalled at the first opportunity.
WARNING!Temporary use spare tires are for emergency use
only. With these tires, do not drive more than 50 mph
(80 km/h). Temporary-use spare tires have limited
tread life. When the tread is worn to the tread wear
indicators, the temporary use spare tire needs to be
replaced. Be sure to follow the warnings, which
apply to your spare. Failure to do so could result in
spare tire failure and loss of vehicle control. Do not install a wheel cover or attempt to mount a
conventional tire on the compact spare wheel, since the
wheel is designed specifically for the compact spare.
Do not install more than one compact spare tire/wheel
on the vehicle at any given time.
CAUTION!Because of the reduced ground clearance, do not take
your vehicle through an automatic car wash with the
compact spare installed. Damage to the vehicle may
result.318 STARTING AND OPERATING

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 30 mph (48 km/h).
Refer to the paragraph on “Freeing A Stuck Vehicle” in
Section 6 of this manual. STARTING AND OPERATING 319
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WARNING!Fast spinning tires can be dangerous. Forces gener-
ated by excessive wheel speeds may cause tire dam-
age or failure. A tire could explode and injure
someone. Do not spin your vehicle’s wheels faster
than 30 mph (48 km/h) for more than 30 seconds
continuously when you are stuck, and don’t let
anyone near a spinning wheel, no matter what the
speed.
Tread Wear Indicators
Tread wear indicators are in the original equipment tires
to help you in determining when your tires should be
replaced. These indicators are molded into the bottom of the tread
grooves. They will appear as bands when the tread depth
becomes 1/16 inch (2 mm). When the tread is worn to the
tread wear indicators, the tire should be replaced.
Many states have laws requiring tire replacement at this
point.320 STARTING AND OPERATING