tires Ram 1500 2011 User Guide

Proper operation of four-wheel drive vehicles depends
on tires of equal size, type and circumference on each
wheel. Any difference in tire size can cause damage to the
drivetrain.
Because four-wheel drive provides improved traction,
there is a tendency to exceed safe turning and stopping
speeds. Do not go faster than road conditions permit.
WARNING!
You or others could be injured if you leave the
vehicle unattended with the transfer case in the
NEUTRAL position without first fully engaging the
parking brake. The transfer case NEUTRAL position
disengages both the front and rear driveshafts from
the powertrain and will allow the vehicle to move
regardless of the transmission position. The parking
brake should always be applied when the driver is
not in the vehicle.For additional information on the appropriate use of each
transfer case mode position, see the information below:
2WD
Rear-Wheel Drive High Range - This range is for normal
street and highway driving on dry hard surfaced roads.
4WD AUTO
Four-Wheel Drive Auto Range - This range sends power
to the rear wheels. The four–wheel drive system will be
automatically engaged when the vehicle senses a loss of
traction. Additional traction for varying road conditions.
4WD LOCK
Four-Wheel Drive Lock Range - This range locks the front
and rear driveshafts together forcing the front and rear
wheels to rotate at the same speed. Additional traction
for loose, slippery road surfaces only.
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CAUTION! (Continued)
•Do not try to lock the rear axle if the vehicle is
stuck and the tires are spinning. You can damage
drivetrain components. Lock the rear axle before
attempting situations or navigating terrain, which
could possibly cause the vehicle to become stuck.
The locking axles are controlled by the axle locker switch.
The switch has three positions, AXLE UNLOCK, REAR
LOCK, and FRONT/REAR LOCK. Under normal driv-
ing conditions, the switch should be left in the AXLE
UNLOCK position. In the AXLE UNLOCK position, the
front and rear axles are unlocked. In the REAR LOCK
position, the rear axle is locked. In the FRONT/REAR
LOCK position, the front and rear axles are locked. NOTE:
Even when the axles are in the AXLE UNLOCK
position, the limited slip differential in the rear axle still
provides torque biasing capability for moderate low
traction environments.
During the command to lock the axle, the indicator light
will flash until the axle is locked. After the lock command
has been successfully executed, the light will remain on
solid.
To lock the rear axle, place the vehicle in 4LO. Refer to
“Four Wheel Drive Operation” in “Starting and Operat-
ing” for further information. Move the axle locker switch
position to REAR LOCK while traveling less than 3 mph
(5 km/h). The RR indicator light will remain on when the
rear axle is locked.
NOTE: Left to right wheel speed difference may be
necessary to allow the axle to fully lock. If the indicator
light is flashing after placing the switch in the REAR
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Driving In Snow, Mud And Sand
There is a drastic reduction in traction when driving in
snow, mud or sand. The vehicle will be less responsive to
steering, acceleration and braking inputs. Therefore you
should accelerate slowly, leave greater stopping distances
and avoid abrupt vehicle maneuvers. You want to keep a
slow constant steady pace. The key is to maintain the
vehicle’s momentum.
•Snow– In heavy snow or for additional control and
traction at slower speeds, shift the transmission to a
low gear and shift the transfer case to 4L (Low Range)
if necessary. Do not shift to a lower gear than neces-
sary to maintain headway. Over-revving the engine
can spin the wheels and traction will be lost. If you
start to slow to a stop, try turning your steering wheel
no more than a
14turn quickly back and forth, while
still applying throttle. This will allow the tires to get a
fresh bite and help maintain your momentum.
CAUTION!
On icy or slippery roads, do not downshift at high
engine RPMs 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 4L (Low Range) with a gear low
enough to maintain your momentum without shifting.
If you start to slow to a stop, try turning your steering
wheel no more than a
14turn 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.
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•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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independently. You need to use caution when crossing
large obstacles with steep sides. Do not attempt to cross
any large obstacle with steep sides at an angle great
enough to put the vehicle at risk of a rollover. If you get
caught in a rut, dig a small trench to the right or left at a
45-degree angle ahead of the front tires. Use the removed
dirt to fill the rut ahead of the turnout you just created.
You should now be able to drive out following the trench
you just created at a 45-degree angle.
WARNING!
There is an increased risk of rollover when crossing
an obstacle, at any angle, with steep sides.
Crossing Logs
To cross a log, approach it at a slight angle (approxi-
mately 10 to 15 degrees). This allows one front tire to be
on top of the log while the other just starts to climb the
log. While climbing the log, modulate your brake andaccelerator to avoid spinning the log out from under your
tires. Then ease the vehicle off the log using your brakes.
CAUTION!
Do not attempt to cross a log with a greater diameter
than the running ground clearance or the vehicle will
become high centered.
Getting High Centered
If you get hung up or high centered on an object, get out
of the vehicle and try to determine what the vehicle is
hung up on, where it is contacting the underbody and
what is the best direction to recover the vehicle. Depend-
ing on what you are in contact with, jack the vehicle up
and place a few rocks under the tires so the weight is off
of the high point when you let the vehicle down. You can
also try rocking the vehicle or winching the vehicle off
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CAUTION!
Winching or rocking the vehicle off hard objects
increases the risk of underbody damage.
Hill Climbing
Hill climbing requires good judgment and a good under-
standing of your abilities and your vehicle’s limitations.
Hills can cause serious problems. Some are just too steep
to climb and should not be attempted. You should always
feel confident with the vehicle and your abilities. You
should always climb hills straight up and down. Never
attempt to climb a hill on an angle.
•Before Climbing A Steep Hill– As you approach a
hill consider its grade or steepness. Determine if it is
too steep. Look to see what the traction is on the hill
side trail. Is the trail straight up and down? What is on
top and the other side? Are there ruts, rocks, branches
or other obstacles on the path? Can you safely recover the vehicle if something goes wrong? If everything
looks good and you feel confident, then change trans-
mission into a lower gear, shift the transfer case into 4L
(Low) and proceed with caution. You should use first
gear and 4L (Low Range) for very steep hills.
•Driving Up Hill
– Once you have determined your
ability to proceed and have shifted into the appropri-
ate gear, line your vehicle up for the straightest
possible run. Accelerate with an easy constant throttle
and apply more power as you start up the hill. Do not
race forward into a steep grade, the abrupt change of
grade could cause you to lose control. If the front end
begins to bounce, ease off the throttle slightly to bring
all four tires back on the ground. As you approach the
crest of the hill ease off the throttle and slowly proceed
over the top. If the wheels start to slip as you approach
the crest of a hill, ease off the accelerator and maintain
headway by turning the steering wheel no more than
a
14turn quickly back and forth. This will provide a
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freshbite into the surface and will usually provide
enough traction to complete the climb. If you do not
make it to the top, place the vehicle in REVERSE and
back straight down the grade using engine resistance
along with the vehicle brakes.
WARNING!
Never attempt to climb a hill at an angle or turn
around on a steep grade. Driving across an incline
increases the risk of a roll over, which may result in
severe injury.
•Driving Down Hill – Before driving down a steep hill
you need to determine if it is too steep for a safe
descent. What is the surface traction? Is the grade too
steep to maintain a slow controlled descent? Are there
obstacles? Is it a straight descent? Is there plenty of
distance at the base of the hill to regain control if the
vehicle descends too fast? If you feel confident in your ability to proceed then make sure you are in 4L (Low
Range) with the transmission in first gear (manually
select first gear on automatic transmissions) and pro-
ceed with caution. Allow engine braking to control the
descent and apply your brakes if necessary, but do not
allow the tires to lock.
WARNING!
Do not descend a steep grade in NEUTRAL. Use
vehicle brakes in conjunction with engine braking.
Descending a grade too fast could cause you to lose
control and be seriously injured.
•Driving Across An Incline
– If at all possible avoid
driving across an incline. If it is necessary, know your
vehicle’s abilities. Driving across an incline places
more weight on the down hill wheels, which increases
the possibilities of a down hill slide or rollover. Make
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sure the surface has good traction with firm and stable
soils. If possible transverse the incline at an angle
heading slightly up or down.
WARNING!
Driving across an incline increases the risk of a
rollover, which may result in severe injury.
•If You Stall Or Begin To Lose Headway– If you stall
or begin to lose headway while climbing a steep hill,
allow your vehicle to come to a stop and immediately
apply the brake. Restart the engine and shift into
REVERSE. Back slowly down the hill allowing the
compression braking of the engine and transmission to
help regulate your speed. If the brakes are required to
control vehicle speed, apply them lightly and avoid
locking or skidding the tires.
WARNING!
If the engine stalls or you lose headway or cannot
make it to the top of a steep hill or grade, never
attempt to turn around. To do so may result in
tipping and rolling the vehicle, which may result in
severe injury. Always back carefully straight down a
hill in REVERSE. Never back down a hill in NEU-
TRAL using only the vehicle brakes. Never drive
diagonally across a hill, always drive straight up or
down.
Driving Through Water
Extreme care should be taken crossing any type of water.
Water crossings should be avoided if possible and only
be attempted when necessary, in a safe responsible
manner. You should only drive through areas which are
designated and approved. You should tread lightly and
avoid damage to the environment. You should know
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crossing is the water depth, current and bottom con-
ditions. On soft bottoms the vehicle will sink in,
effectively increasing the water level on the vehicle. Be
sure to consider this when determining the depth and
the ability to safely cross.
•Crossing Puddles, Pools, Flooded Areas Or Other
Standing Water– Puddles, pools, flooded or other
standing water areas normally contain murky or
muddy waters. These water types normally contain
hidden obstacles and make it difficult to determine an
accurate water depth, approach angle, and bottom
condition. Murky or muddy water holes are where
you want to hook up tow straps prior to entering. This
makes for a faster, cleaner and easier vehicle recovery.
If you are able to determine you can safely cross, than
proceed using the low and slow method.
CAUTION!
Muddy waters can reduce the cooling system effec-
tiveness by depositing debris onto the radiator.
•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
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