tires Ram 3500 2011 User Guide

CAUTION!
•Do not lock the front or rear axle on hard surfaced
roads. The ability to steer the vehicle is reduced
and damage to the drivetrain may occur when the
axles are locked on hard surfaced roads.
•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 LOCKposition, 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.
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no more than a14turn quickly back and forth, while
still applying throttle. This will allow the tires to get a
freshbiteand 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 mudhole, 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 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.
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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 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 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 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 obstacleindependently. 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 and
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accelerator 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
the object.
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
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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 afreshbiteinto 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
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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. Makesure 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
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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 vehicledownstream 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 or
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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
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? Is there an anchor point to winch to? 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
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vehicle impingement on the surroundings, then using a
tow strap to the vehicle tow hooks would be fast and
easy. If the vehicle is severely hung up or in a situation
where great care needs to be taken during the recovery,
then nothing can do the job better than a winch. If you are
severely hung up on something you should jack the
vehicle up and stack something under the wheels to
allow the vehicle to roll off the object without causing
further damage. This should be tried before attempting
any recovery method.
CAUTION!
Pulling the vehicle off an obstacle, without first
clearing the object, may result in additional under-
body damage.
•Rock Cycling Your Vehicle– Rock cycling your ve-
hicle is one of the easiest, fastest and most commonly
used methods. This simply involves shifting yourvehicle from DRIVE to REVERSE, while applying
throttle after each shift. During this process, for addi-
tional traction, try turning your steering wheel quickly
back and forth no more than a
14turn. If you are stuck
in mud, sand, or snow try spinning your tires during
this process to clean the debris from the tread and
improve the traction. You want to create a rocking
motion with the vehicle. This helps build vehicle
momentum, which hopefully gets you out. Remember
to ease off and on the accelerator before and after the
shift. If after a few rock cycles your vehicle is not free,
stop and try another method of recovery. Continuous
rock cycling will only cause unnecessary damage to
your vehicle and the environment.
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