inflation pressure RAM CHASSIS CAB 2011 Owners Manual

Wind Buffeting
Wind buffeting can be described as the perception of
pressure on the ears or a helicopter-type sound in the
ears. Your vehicle may exhibit wind buffeting with the
windows down or in partially open positions. This is a
normal occurrence and can be minimized. If the buffeting
occurs with the rear windows open, open the front and
rear windows together to minimize the buffeting.
OCCUPANT RESTRAINTS
Some of the most important safety features in your
vehicle are the restraint systems:
• Three-point lap and shoulder belts for the driver and
all passengers
• Advanced Front Airbags for driver and front passen-
ger — if equipped
• An energy-absorbing steering column and steering
wheel • Knee bolsters/blockers for front seat occupants
• All seat belt systems (except driver’s, first and second
row center position) include Automatic Locking Re-
tractors (ALR)
If you will be carrying children too small for adult-sized
seat belts, the seat belts or the Lower Anchors and Tether
for CHildren (LATCH) feature also can be used to hold
infant and child restraint systems.
NOTE: The Advanced Front Airbags have a multistage
inflator design. This allows the airbag to have different
rates of inflation based on the severity and type of
collision.
Please pay close attention to the information in this
section. It tells you how to use your restraint system
properly, to keep you and your passengers as safe as
possible. 2 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 37

▫ Electronically Shifted Transfer Case
(Four-Position Switch) – If Equipped ....... 278
▫ Shifting Procedure ................... 282
 Limited-Slip Differential ................. 284
 Driving On Slippery Surfaces ............. 285
 Driving Through Water ................. 285
▫ Flowing/Rising Water ................. 286
▫ Shallow Standing Water ............... 286
 Power Steering ....................... 288
▫ Power Steering Fluid Check ............. 289
 Parking Brake ........................ 289
 Brake System ........................ 292
▫ Dual Rear Wheel Models Only ........... 292 ▫ Four-Wheel Anti-Lock Brake System ....... 292
 Tire Safety Information ................. 294
▫ Tire Markings ....................... 294
▫ Tire Identification Number (TIN) ......... 298
▫ Tire Terminology And Definitions ......... 299
▫ Tire Loading And Tire Pressure .......... 300
 Tires — General Information ............. 304
▫ Tire Pressure ....................... 304
▫ Tire Inflation Pressures ................ 305
▫ Radial Ply Tires ..................... 309
▫ Tire Spinning ....................... 309
▫ Tread Wear Indicators ................. 310
▫ Life Of Tire ........................ 310260 STARTING AND OPERATING

EXAMPLE:
Service Description:
95 = Load Index
— A numerical code associated with the maximum load a tire can carry
H = Speed Symbol
— A symbol indicating the range of speeds at which a tire can carry a load corresponding
to its load index under certain operating conditions
— The maximum speed corresponding to the speed symbol should only be achieved under
specified operating conditions (i.e., tire pressure, vehicle loading, road conditions, and
posted speed limits)
Load Identification:
 ....blank....  = Absence of any text on the sidewall of the tire indicates a Standard Load (SL) tire
Extra Load (XL) = Extra load (or reinforced) tire
Light Load = Light load tire
C, D, E = Load range associated with the maximum load a tire can carry at a specified pressure
Maximum Load — Maximum load indicates the maximum load this tire is designed to carry
Maximum Pressure — Maximum pressure indicates the maximum permissible cold tire inflation pressure for
this tire
5 STARTING AND OPERATING 297

Tire Terminology and Definitions
Term Definition
B-Pillar The vehicle B-Pillar is a structural member of the body located
between the front and rear door (of a four-door vehicle) running
from the sill to the roof.
Cold Tire 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 (1.6 km) after sitting for a three hour period. Inflation
pressure is measured in units of PSI (pounds per square inch) or
KPa (kilopascals).
Maximum Inflation Pressure The maximum inflation pressure is the maximum permissible cold
tire inflation pressure for this tire. The max inflation pressure is
molded into the sidewall.
Recommended Inflation Pressure Vehicle manufacturer’s recommended tire inflation pressure as
shown on the tire placard.
Tire Placard A paper label permanently attached to the vehicle showing the
vehicle’s loading capacity, the original equipment tire size and the
recommended inflation pressure.
5 STARTING AND OPERATING 299

Tire Loading and Tire Pressure
Tire Placard Location
NOTE: The proper cold tire inflation pressure is listed
on the driver’s side B-Pillar. Tire and Loading Information Placard
Tire Placard Location Tire and Loading Information Placard300 STARTING AND OPERATING

This placard tells you important information about
the:
1) number of people that can be carried in the vehicle
2) total weight your vehicle can carry
3) tire size designed for your vehicle
4) cold tire inflation pressures for the front, rear, and
spare tires.
Loading
The vehicle maximum load on the tire must not exceed
the load carrying capacity of the tire on your vehicle. You
will not exceed the tire’s load carrying capacity if you
adhere to the loading conditions, tire size, and cold tire
inflation pressures specified on the Tire and Loading
Information placard and in the “Vehicle Loading” section
of this manual. NOTE: Under a maximum loaded vehicle condition,
gross axle weight ratings (GAWRs) for the front and rear
axles must not be exceeded. For further information on
GAWRs, vehicle loading, and trailer towing, refer to
“Vehicle Loading” in this section.
To determine the maximum loading conditions of your
vehicle, locate the statement “The combined weight of
occupants and cargo should never exceed XXX lbs or
XXX kg” on the Tire and Loading Information placard.
The combined weight of occupants, cargo/luggage and
trailer tongue weight (if applicable) should never exceed
the weight referenced here.
Steps for Determining Correct Load Limit
1. Locate the statement “The combined weight of occu-
pants and cargo should never exceed XXX lbs or XXX kg”
on your vehicle’s placard.
5 STARTING AND OPERATING 301

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: Safety
WARNING!• Improperly inflated tires are dangerous and can
cause accidents.
• Under-inflation increases tire flexing and can re-
sult 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 ve-
hicle to the other can cause the vehicle to drift to
the right or left.
(Continued)304 STARTING AND OPERATING

WARNING! (Continued)• Always drive with each tire inflated to the recom-
mended cold tire inflation pressure.
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 consumption.
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 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
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. This will prevent
moisture and dirt from entering the valve stem,
which could damage the valve stem.
5 STARTING AND OPERATING 305

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 three hours, or driven less than
1 mile (1.6 km) after a three hour period. The cold tire
inflation pressure must not exceed the maximum infla-
tion pressure 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.
Tire Inflation Pressure – 4500/5500 with Steel
Carcass Ply Tires
This type of tire utilizes steel cords in the sidewall. As
such, they cannot be treated like normal light truck tires.
Adjusting tire pressure must be performed by personnel
trained, supervised and equipped accordingly.
Inflation Pressure Adjustment When Mounted to
Vehicle
During procedures when adding tire inflation pressure,
the technician or individual must utilize a remote infla-
tion device, and ensure that all persons are clear of the
trajectory area.306 STARTING AND OPERATING

When adjusting inflation pressure to a tire and wheel
assembly mounted on a vehicle, use a Remote Mount
Automatic Inflation Kit or see your authorized dealer.
NOTE: Never attempt to re-inflate a tire and wheel
assembly which has been run flat or is extremely under-
inflated without first removing the tire from the wheel
assembly for inspection.
Personnel trained, supervised, and equipped according
to Federal Occupational Safety and Health Administra-
tion (OSHA) should perform this work.
Inflation Pressure Adjustment When Not Mounted to
Vehicle
When adjusting inflation pressure to a tire and wheel
assembly not mounted on a vehicle, use a Remote Mount
Automatic Inflation Kit and a Tire Inflation Cage or see
your authorized dealer. 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 resulting in serious injury or death.
Don’t drive a vehicle loaded to the maximum capac-
ity at continuous speeds above 75 mph (120 km/h).308 STARTING AND OPERATING