tire pressure Ram 1500 2011 User Guide

•Sand– Soft sand is very difficult to travel through
with full tire pressure. When crossing soft sandy spots
in a trail maintain your vehicle’s momentum and do
not stop. The key to driving in soft sand using the
appropriate tire pressure, accelerating slowly, avoid-
ing abrupt maneuvers and maintaining the vehicle’s
momentum. If you are going to be driving on large soft
sandy areas or dunes, reduce your tire pressure to a
minimum of 15 psi (103 kPa) to allow for a greater tire
surface area. Reduced tire pressure will drastically
improve your traction and handling, while driving on
the soft sand, but you must return the tires to normal
air pressure before driving on pavement or other hard
surfaces. Be sure you have a way to air the tires back
up prior to reducing the pressure.CAUTION!
Reduced tire pressures may cause tire unseating and
total loss of air pressure. To reduce the risk of tire
unseating, while at a reduced tire pressure, reduce
your speed and avoid sharp turns or abrupt maneu-
vers.
Crossing Obstacles (Rocks And Other High
Points)
While driving off road, you will encounter many types of
terrain. These varying types of terrain bring different
types of obstacles. Before proceeding review the path
ahead to determine the correct approach and your ability
to safely recover the vehicle if something goes wrong.
Keeping a firm grip on the steering wheel, bring the
vehicle to a complete stop and then inch the vehicle
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forward until it makes contact with the object. Apply the
throttle lightly while holding a light brake pressure and
ease the vehicle up and over the object.
WARNING!
Crossing obstacles can cause abrupt steering system
loading which could cause you to loose control of
your vehicle.
Using A Spotter
There are many times where it is hard to see the obstacle
or determine the correct path. Determining the correct
path can be extremely difficult when you are confronting
many obstacles. In these cases have someone guide you
over, through, or around the obstacle. Have the person
stand a safe distance in front of you where they can see
the obstacle, watch your tires and undercarriage, and
guide you through.
Crossing Large Rocks
When approaching large rocks, choose a path which
ensures you drive over the largest with your tires. This
will lift your undercarriage over the obstacle. The tread of
the tire is tougher and thicker than the side wall and is
designed to take the abuse. Always look ahead and make
every effort to cross the large rocks with your tires.
CAUTION!
•Never attempt to straddle a rock that is large
enough to strike your axles or undercarriage.
•Never attempt to drive over a rock which is large
enough to contact the door sills.
Crossing A Ravine, Gully, Ditch, Washout Or Rut
When crossing a ravine, gully, ditch, washout or a large
rut, the angled approach is the key to maintaining your
vehicle’s mobility. Approach these obstacles at a 45-
degree angle and let each tire go through the obstacle
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downstream out of control if the water is deep enough
to push on the large surface area of the vehicle’s body.
Before you proceed determine the speed of the current,
the water’s depth, approach angle, bottom condition
and if there are any obstacles, then cross at an angle
heading slightly upstream using the low and slow
technique.
WARNING!
Never drive through fast moving deep water. It can
push your vehicle downstream, sweeping it out of
control. This could put you and your passengers at
risk of injury or drowning.
Airing Down For Off-Road Driving
Running lower tire pressure off-road can improve your
ride comfort and vehicle traction. Reducing the tire air
pressure allows the tire to bulge slightly, improving its
surface area for better flotation and ability to mold orform to the ground contour. Different terrain, tires, and
vehicles require different tire pressure. Hard surfaces like
rock and heavier vehicles require higher pressures than
softer surfaces such as sand and lighter vehicles. You will
need to experiment to determine what is right for your
situation. It is easier and faster to let air out than it is to
replace it so, start high and lower it as required. Remem-
ber you must return the tires to normal air pressure
before driving on road or at highway conditions. Be sure
you have a way to return the tires to their normal on road
air pressure.
CAUTION!
Reduced tire pressure increases the risk of tire dam-
age and may cause tire unseating with total loss of air
pressure. To reduce the risk of tire unseating, while at
a reduced tire pressure, drive at slower speeds and
avoid sharp turns or abrupt maneuvers.
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OFF-ROAD DRIVING TIPS
Care should be taken when attempting to climb steep
hills or driving diagonally across a hill or slope. If natural
obstacles force you to travel diagonally up or down a hill,
choose a mild angle and keep as little side tilt as possible.
Keep the vehicle moving and make turns slowly and
cautiously.
If you must back down a hill, back straight down using
REVERSE gear. Never back down in NEUTRAL or diago-
nally across the hill.
When driving over sand, mud, and other soft terrain,
shift to low gear and drive steadily. Apply the accelerator
slowly to avoid spinning the wheels.
Do not reduce the tire pressures for this type of driving.
After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road, it isalways a good idea to check for damage. That way you
can get any problems taken care of right away and have
your vehicle ready when you need it.
•Completely inspect the underbody of your vehicle.
Check tires, body structure, steering, suspension, and
exhaust system for damage.
•Inspect the radiator for mud and debris and clean as
required.
•Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering, and sus-
pension. Retighten them, if required, and torque to the
values specified in the Service Manual.
•Check for accumulations of plants or brush. These
things could be a fire hazard. They might hide damage
to fuel lines, brake hoses, axle pinion seals, and
propeller shafts.
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NOTE:Under cold temperatures, pedal effort will be
higher than normal until the power steering fluid reaches
operating temperature.
ELECTRONIC BRAKE CONTROL SYSTEM
Your vehicle is equipped with an advanced electronic
brake control system that includes Anti-Lock Brake Sys-
tem (ABS), Traction Control System (TCS), Brake Assist
System (BAS), Hill Start Assist (HSA), Electronic Stability
Control (ESC) and Trailer Sway Control (TSC). All of the
systems work together to enhance vehicle stability and
control in various driving conditions, and are commonly
referred to as ESC.
Anti-Lock Brake System (ABS)
The ABS aids the driver in maintaining vehicle control
under adverse braking conditions. The system controls
hydraulic brake pressure to prevent wheel lockup and
help avoid skidding on slippery surfaces during braking. NOTE:
ABS improves steering control of the vehicle
during hard braking maneuvers.
WARNING!
•ABS cannot prevent the natural laws of physics
from acting on the vehicle, nor can it increase
braking or steering efficiency beyond that af-
forded by the condition of the vehicle brakes and
tires or the traction afforded.
•The ABS cannot prevent collisions, including
those resulting from excessive speed in turns,
following another vehicle too closely, or hydro-
planing.
•The capabilities of an ABS-equipped vehicle must
never be exploited in a reckless or dangerous
manner which could jeopardize the user’s safety
or the safety of others.
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WARNING!
•The BAS cannot prevent the natural laws of phys-
ics from acting on the vehicle, nor can it increase
braking efficiency beyond that afforded by the
condition of the vehicle brakes and tires or the
traction afforded.
•The BAS cannot prevent collisions, including
those resulting from excessive speed in turns,
following another vehicle too closely, or hydro-
planing.
•The capabilities of a BAS-equipped vehicle must
never be exploited in a reckless or dangerous
manner which could jeopardize the user ’s safety
or the safety of others.
Hill Start Assist (HSA) – If Equipped
The HSA system is designed to assist the driver in
launching a vehicle on an incline. HSA will maintain thelevel of brake pressure the driver inputs for a short
duration once the driver takes his foot off of the brake
pedal. If the driver does not apply the throttle during this
short duration, the system will release brake pressure
and the vehicle will roll down the incline. The system will
release brake pressure in proportion to the amount of
throttle applied.
During operation, HSA will activate the brake control
system and a clicking noise may occur. If your foot is on
the brake pedal during operation you may feel a slight
pedal movement. The clicking and pedal movement is
normal and both will stop when HSA becomes inactive.
HSA Activation Criteria
The following criteria must be met in order for HSA to
activate:
•Vehicle must be stopped
•Vehicle must be on a 7% or greater incline
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TIRE SAFETY INFORMATION
Tire MarkingsNOTE:
•P (Passenger) - Metric tire sizing is based on U.S.
design standards. P-Metric tires have the letter “P”
molded into the sidewall preceding the size designa-
tion. Example: P215/65R15 95H.
•European-Metric tire sizing is based on European
design standards. Tires designed to this standard have
the tire size molded into the sidewall beginning with
the section width. The letterPis absent from this tire
size designation. Example: 215/65R15 96H.
•LT (Light Truck) - Metric tire sizing is based on U.S.
design standards. The size designation for LT-Metric
tires is the same as for P-Metric tires except for the
letters “LT” that are molded into the sidewall preced-
ing the size designation. Example: LT235/85R16.
•Temporary spare tires are high-pressure compact
spares designed for temporary emergency use only.
1 — U.S. DOT Safety Stan-
dards Code (TIN) 4 — Maximum Load
2 — Size Designation 5 — Maximum Pressure
3 — Service Description 6 — Treadwear, Traction and Temperature Grades
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EXAMPLE:
15 = Rim diameter in inches (in)
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
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Tire Terminology And Definitions
TermDefinition
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.
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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
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.
Tire Placard Location
Tire and Loading Information Placard
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