tire pressure JEEP PATRIOT 2008 1.G User Guide

CAUTION!
On icy or slippery roads, do not downshift at high
engine RPM’s or vehicle speeds because engine brak-
ing may cause skidding and loss of control.
•Mud–Deep mud creates a great deal of suction around
the tires and is very difficult to get through. You should
use low (L Off-Road) with the 4WD LOCK engaged and
maintain your momentum. If you start to slow to a stop,
try turning your steering wheel no more than a 1/4 turn
quickly back and forth for additional traction. Mud
holes pose an increased threat of vehicle damage and
getting stuck. They are normally full of debris from
previous vehicles getting stuck. As a good practice
before entering any mud hole, get out and determine
how deep it is, if there are any hidden obstacles and if
the vehicle can be safely recovered if stuck.
•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 is 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. You should use low (L Off-Road) with the
4WD LOCK engaged and ESP turned off. 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 reinflate the tires prior to reducing the
pressure.
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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
maneuvers.
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 vehicleforward 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.
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•Crossing Ditches, Streams, Shallow Rivers Or Other
Flowing Water– Flowing water can be extremely
dangerous. Never attempt to cross a fast running
stream or river even in shallow water. Fast moving
water can easily push your vehicle downstream
sweeping it out of control. Even in very shallow water,
a high current can still wash the dirt out from around
your tires putting you and your vehicle in jeopardy.
There is still a high risk of personal injury and vehicle
damage with slower water currents in depths greater
than the vehicle’s running ground clearance. You
should never attempt to cross flowing water which is
deeper than the vehicle’s running ground clearance.
Even the slowest current can push the heaviest vehicle
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 conditionand 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 or
form to the ground contour. Different terrain, tires, and
vehicles require different tire pressure. Hard surfaces like
rock and heavier vehicles require higher pressures than
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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.
Vehicle Recovery
If you drive off-road, you may encounter a situation
where you will need to recover your vehicle. Vehicle
recovery should always be given consideration before
attempting a questionable obstacle. You should never go
off-road driving without the ability to recover your
vehicle from a situation. Having another vehicle with
you usually works best for most situations. The first
thing to do is assess the situation. Why are you stuck?
Are you hung up on something? Would it be easier to go
forward or to go backward? Can you still move the
vehicle? Are you alone or do you have another vehicle to
help? Is there high risk of vehicle damage during the
recovery process? Answering these questions will help
you determine the best method of recovery. If you can
still move the vehicle slightly and the only issue is slick
ground, then rock cycling your vehicle would be the first
choice. If you have ample room, an additional vehicle
and there is low risk of vehicle impingement on the
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TIRE SAFETY INFORMATION
TIRE MARKINGS
NOTE:
•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.
Tires designed to this standard have the letter “T”
molded into the sidewall preceding the size designa-
tion. Example: T145/80D18 103M.
•High flotation tire sizing is based on U.S. design
standards, and it begins with the tire diameter molded
into the sidewall. Example: 31x10.5 R15 LT.
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TIRE SIZING TERMS
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 LOADING AND TIRE PRESSURE
Tire Placard Location
NOTE:The proper cold tire inflation pressure is listed
on either the face of the driver’s door or 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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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 kg or XXX
lbs.” on the Tire and Loading Information placard. Thecombined 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 kg or XXX lbs”
on your vehicle’s placard.
2. Determine the combined weight of the driver and
passengers that will be riding in your vehicle.
3. Subtract the combined weight of the driver and pas-
sengers from XXX kg or XXX lbs.
4. The resulting figure equals the available amount of
cargo and luggage load capacity. For example, if “XXX”
amount equals 1,400 lbs (635 kg) and there will be five
150 lb (68 kg) passengers in your vehicle, the amount of
available cargo and luggage load capacity is 650 lbs (295
kg) (since 5 x 150 = 750, and 1400 – 750 = 650 lbs [295 kg]).
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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.
WARNING!
•Over-inflation reduces a tire’s ability to cushion
shock. Objects on the road and chuckholes can cause
damage that result in tire failure.
•Over-inflated or under-inflated tires can affect ve-
hicle handling and can fail suddenly, resulting in
loss of vehicle control.
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WARNING!
•Unequal tire pressures can cause steering problems.
You could lose control of your vehicle.
•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.
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.
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