wheel Ram 3500 2011 Repair Manual

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high water fording characteristics with the ability to cross
a pool of water, without stopping, 24 inches deep at a
maximum speed of 10 mph (16 km/h) and a pool of
water 30 inches deep at a maximum speed of 5 mph
(8 km/h), both with an entrance ramp angle of 1.3
degrees.
CAUTION!
The door sill height is 25 inches. Water may intrude
into the interior of the vehicle at greater depths.
Simultaneous Brake And Throttle Operation
Many off-road driving conditions require the simulta-
neous use of the brake and throttle (two footed driving).
When climbing rocks, logs, or other stepped objects,
using light brake pressure with light throttle will keep the
vehicle from jerking or lurching. This technique is also
used when you need to stop and restart a vehicle on a
steep incline.
The Basics Of Off-Road Driving
You will encounter many types of terrain driving off-
road. You should be familiar with the terrain and area
before proceeding. There are many types of surface
conditions: hard packed dirt, gravel, rocks, grass, sand,
mud, snow and ice. Every surface has a different effect on
your vehicle’s steering, handling and traction. Control-
ling your vehicle is one of the keys to successful off-road
driving, so always keep a firm grip on the steering wheel
and maintain a good driving posture. Avoid sudden
accelerations, turns or braking. In most cases there are no
road signs, posted speed limits or signal lights. Therefore
you will need to use your own good judgment on what is
safe and what isn’t. When on a trail you should always be
looking ahead for surface obstacles and changes in
terrain. The key is to plan your future driving route while
remembering what you are currently driving over.
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CAUTION!
Never park your vehicle over dry grass or other
combustible materials. The heat from your vehicle
exhaust system could cause a fire.
WARNING!
Always wear your seat belt and firmly tie down
cargo. Unsecured cargo can become projectiles in an
off-road situation.
When To Use Low Range
When driving off-road, shift into 4L (Low Range) for
additional traction or to improve handling and control on
slippery or difficult terrain. Due to the lower gearing, low
range will allow the engine to operate in a higher power
range. This will allow you to idle over obstacles and
down hills, with improved control and less effort. Also,use 4L (Low Range) in rain, ice, snow, mud, sand, to get
heavy loads rolling, improve traction, or whenever 4H
(High Range) traction will not do the job.
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
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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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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
locking or skidding the tires.5
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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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•After extended operation in mud, sand, water, or
similar dirty conditions, have the radiator, fan, brake
rotors, wheels, brake linings, and axle yokes inspected
and cleaned as soon as possible.
WARNING!
Abrasive material in any part of the brakes may cause
excessive wear or unpredictable braking. You might
not have full braking power when you need it to
prevent a collision. If you have been operating your
vehicle in dirty conditions, get your brakes checked
and cleaned as necessary.
•If you experience unusual vibration after driving in
mud, slush or similar conditions, check the wheels for
impacted material. Impacted material can cause a
wheel imbalance and freeing the wheels of it will
correct the situation.
LIMITED-SLIP DIFFERENTIAL
The limited-slip differential provides additional traction
on snow, ice, mud, sand and gravel, particularly when
there is a difference between the traction characteristics
of the surface under the right and left rear wheels. During
normal driving and cornering, the limited-slip unit per-
forms similarly to a conventional differential. On slip-
pery surfaces, however, the differential delivers more of
the driving effort to the rear wheel having the better
traction.
The limited-slip differential is especially helpful during
slippery driving conditions. With both rear wheels on a
slippery surface, a slight application of the accelerator
will supply maximum traction. When starting with only
one rear wheel on an excessively slippery surface, slight
momentary application of the parking brake may be
necessary to gain maximum traction.
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WARNING!
On vehicles equipped with a limited-slip differential
never run the engine with one rear wheel off the
ground since the vehicle may drive through the rear
wheel remaining on the ground. You could lose
control of the vehicle.
Care should be taken to avoid sudden accelerations when
both rear wheels are on a slippery surface. This could
cause both rear wheels to spin, and allow the vehicle to
slide sideways on the crowned surface of a road or in a
turn.
DRIVING ON SLIPPERY SURFACES
Acceleration
Rapid acceleration on snow covered, wet, or other slip-
pery surfaces may cause the rear wheels to pull errati-
cally to the right or left. This phenomenon occurs when
there is a difference in the surface traction under the rear
(driving) wheels.
WARNING!
Rapid acceleration on slippery surfaces is dangerous.
Unequal traction can cause sudden pulling of the rear
wheels. You could lose control of the vehicle and
possibly have a collision. Accelerate slowly and
carefully whenever there is likely to be poor traction
(ice, snow, wet mud, loose sand, etc.).
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WARNING!
•Driving through standing water limits your vehi-
cle’s traction capabilities. Do not exceed 5 mph
(8 km/h) when driving through standing water.
•Driving through standing water limits your vehi-
cle’s braking capabilities, which increases stop-
ping distances. Therefore, after driving through
standing water, drive slowly and lightly press on
the brake pedal several times to dry the brakes.
•Getting water inside your vehicle’s engine can
cause it to lock up and stall out, and leave you
stranded.
•Failure to follow these warnings may result in
injuries that are serious or fatal to you, your
passengers, and others around you.
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 is
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