2015 Ram 3500 wheel torque

This electronically shifted transfer case provides five
mode positions:
•Two-wheel drive high range (2WD)
• Four-wheel drive automatic range (4WD AUTO)
• Four-wheel drive lock range (4WD LOCK)
• Four-wheel drive low range (4WD LOW)
• Neutral (NEUTRAL)
This electronically shifted transfer case is designed to be
driven in the two–wheel drive position (2WD) or four-
wheel drive position (4WD AUTO) for normal street and
highway conditions on dry hard surfaced roads). Driving
the vehicle in 2WD will have greater fuel economy
benefits as the front axle is not engaged in 2WD.
For variable driving conditions, the 4WD AUTO mode
can be used. In this mode, the front axle is engaged, but
the vehicle’s power is sent to the rear wheels. Four-wheel drive will be automatically engaged when the vehicle
senses a loss of traction. Because the front axle is en-
gaged, this mode will result in lower fuel economy than
the 2WD mode.
When additional traction is required, the transfer case
4WD LOCK and 4WD LOW positions can be used to
maximize torque to the front driveshaft, forcing the front
and rear wheels to rotate at the same speed. This is
accomplished by rotating the 4WD Control Switch to the
desired position. Refer to “Shifting Procedure” for spe-
cific shifting instructions. The 4WD LOCK and 4WD
LOW positions are designed for loose, slippery road
surfaces only. Driving in the 4WD LOCK and 4WD LOW
positions on dry hard surfaced roads may cause in-
creased tire wear and damage to the driveline compo-
nents.
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WARNING!
You or others could be injured or killed 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 drive shafts from
the powertrain and will allow the vehicle to roll,
even if the transmission is in PARK. 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 maximizes
torque to the front driveshaft, forcing the front and rear
wheels to rotate at the same speed. Additional traction
for loose, slippery road surfaces only.
4WD LOW
Four-Wheel Drive Low Range - This range provides low
speed four-wheel drive. It maximizes torque to the front
driveshaft, forcing the front and rear wheels to rotate at
the same speed. This range provides additional traction
and maximum pulling power for loose, slippery road
surfaces only. Do not exceed 25 mph (40 km/h).
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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
LOCK or FRONT/REAR LOCK position, drive the ve-
hicle in a turn or on loose gravel to expedite the locking
action.
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WARNING!
Do not use the locked axle position for normal
driving. A locked front axle is intended for off-road
driving only. Locking the front axle during on-road
driving will reduce the steering ability. This could
cause a collision and you may be seriously injured.
To lock the front axle; move the axle locker switch to
FRONT/REAR LOCK while traveling less than 3 mph
(5 km/h). The indicator light will be solid when the front
axle is locked.
NOTE: The rear axle must be locked before the front axle
will lock.
To unlock the front axle; move the axle locker switch to
REAR LOCK. The FRONT/REAR LOCK indicator light
will go out when the axle is unlocked. NOTE:
The axle lockers could be torque locked due to
side to side loads on the axle. Driving slowly while
turning the steering wheel from a left hand turn to a right
hand turn or driving in REVERSE for a short distance
may be required to release the torque lock and unlock the
axles.
To unlock the rear axle; move the axle locker switch to
AXLE UNLOCK. The REAR LOCK indicator light will go
out when the rear axle is unlocked.
STABILIZER/SWAY BAR SYSTEM — POWER
WAGON ONLY
Your vehicle is equipped with an electronic disconnecting
stabilizer/sway bar. This system allows greater front
suspension travel in off-road situations.
Due to the use of taller springs, this vehicle has an
increased ride height of approximately 1.9 in (48.3 mm)
in the front and 1.5 in (38.1 mm) in the rear. A major
524 STARTING AND OPERATING

To disconnect the stabilizer/sway bar, shift to either 4HI
or 4LO as shown in “Four Wheel Drive Operation” and
press the right hand Off Road stabilizer/sway bar button
to obtain the Off-Road position. The amber indicator
light will flash until the stabilizer/sway bar has been
fully disconnected.
NOTE:The stabilizer/sway bar may be torque locked
due to left and right suspension height differences. This
condition is due to driving surface differences or vehicle
loading. In order for the stabilizer/sway bar to
disconnect/reconnect, the right and left halves of the bar
must be aligned. This alignment may require that the
vehicle be driven onto level ground or rocked from side
to side.
To return to the On-Road mode; press the left hand On
Road stabilizer/sway bar button.WARNING!
If the stabilizer/sway bar will not return to On-Road
mode, vehicle stability is greatly reduced. Do not
attempt to drive the vehicle over 18 mph (29 km/h).
Driving faster than 18 mph (29 km/h) may cause loss
of control of the vehicle, which could result in
serious injury or death. Contact your local service
center for assistance.
SAFE OFF-ROAD DRIVING — POWER WAGON
ONLY
Off-Road Driving Tips And Vehicle Characteristics
Your vehicle has excellent on and off-road capabilities.
These off-road capabilities will allow you to explore
those wilderness trails where few travel, providing a
source of exciting and satisfying recreation. Before you
venture out, you should contact your local governmental
526 STARTING AND OPERATING

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
always 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.
• 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.
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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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WARNING!(Continued)
efficiency beyond that afforded 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 hydroplaning.
• 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.
ABS Warning Light
The ABS includes an amber warning light. When the light
is illuminated, the ABS is not functioning. The system
reverts to standard, non-anti-lock brakes.
Traction Control System (TCS)
The TCS monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, brake pressure is applied to the slipping wheel(s), and engine
power is reduced to provide enhanced acceleration and
stability. A feature of the TCS system, Brake Limited
Differential (BLD), controls the wheel spin across a
driven axle. If one wheel on a driven axle is spinning
faster than the other, the system will apply the brake of
the spinning wheel. This will allow more engine torque
to be applied to the wheel that is not spinning. This
feature remains active even if TCS and ESC are in the
“Partial Off” mode. Refer to “Electronic Stability Control
(ESC)” in this section of this manual. This brake pressure
modulation transfers drive torque from slipping to non-
slipping wheels to provide optimal forward traction.
Brake Assist System (BAS)
The BAS is designed to optimize the vehicle’s braking
capability during emergency braking maneuvers. The
BAS detects an emergency braking situation by sensing
the rate and amount of brake application and then
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