4L
Four-Wheel Drive Low Range — This range locks the front
and rear driveshafts together forcing the front and rear
wheels to rotate at the same speed. Additional traction and
maximum pulling power for loose, slippery road surfaces
only. Do not exceed 25 mph (40 km/h).
This transfer case is intended to be driven in the 2H
position for normal street and highway conditions such as
dry, hard surfaced roads.
When additional traction is required, the 4H and 4L
positions can be used to lock the front and rear driveshafts
together and force the front and rear wheels to rotate at the
same speed. This is accomplished by simply moving the
gear selector to the desired positions once the appropriate
speed and gear requirements are met, refer to “Shifting
Procedure – Manually Shifted Transfer Case” in this section
for further information.
The 4H and 4L positions are intended for loose, slippery
road surfaces only. Driving in the 4H and 4L positions on
dry, hard surfaced roads may cause increased tire wear and
damage to the driveline components.
The “Transfer Case Position Indicator Light” in the instru-
ment cluster will alert the driver that the vehicle is infour-wheel drive and that the front and rear driveshafts are
locked together. This light will illuminate when the transfer
case is shifted into either the 4H or 4L position. There is no
light for the 2H or NEUTRAL positions on some models.
When operating your vehicle in 4L, the engine speed is
approximately three times that of the 2H or 4H positions at
a given road speed. Take care not to overspeed the engine
and do not exceed 25 mph (40 km/h).
Proper operation of four-wheel drive vehicles depends on
tires of equal size, type and circumference on each wheel.
Any difference will adversely affect shifting and can cause
damage to the drivetrain.
NOTE:
Do not attempt to make a shift while only the front
or rear wheels are spinning, as this can cause damage to
driveline components.
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.
NOTE: Delayed shifts out of four-wheel drive may be
experienced due to uneven tire wear, low or uneven tire
pressures, excessive vehicle loading, or cold temperatures.
258 STARTING AND OPERATING
2H Or 4H To 4L
NOTE:When shifting into or out of 4L some gear noise
may be heard. This noise is normal and is not detrimental
to the vehicle or occupants.
With the vehicle rolling at 2 to 3 mph (3 to 5 km/h), shift
the transmission into NEUTRAL. While the vehicle is
coasting at 2 to 3 mph (3 to 5 km/h), shift the transfer case
lever firmly to the desired position. Do not pause in
transfer case NEUTRAL.
NOTE:
•
Pausing in transfer case NEUTRAL in vehicles equipped
with an automatic transmission may require shutting the
engine OFF to avoid gear clash while completing the shift.
If difficulty occurs, shift the transmission into NEUTRAL,
hold your foot on the brake, and turn the engine OFF.
Complete the range shift to the desired mode.
•Shifting into or out of 4L is possible with the vehicle
completely stopped, however difficulty may occur due to
the mating clutch teeth not being properly aligned. Several
attempts may be required for clutch teeth alignment and
shift completion to occur. The preferred method is with
the vehicle rolling 2 to 3 mph (3 to 5 km/h). Avoid
attempting to engage or disengage 4L with the vehicle
moving faster than 2 to 3 mph (3 to 5 km/h).
• Do not attempt to shift into or out of 4L while the
transmission is in gear.
Transfer Case Position Indicator Light
The “Transfer Case Position Indicator Light” in the instru-
ment cluster is used to alert the driver that the front axle is
fully engaged and all four wheels are driving.
Electronically Shifted Transfer Case (Four-Position
Switch) — If Equipped
The electronic shift transfer case is operated by the 4WD
Control Switch (Transfer Case Switch), which is located on
the instrument panel.
Four-Position/Part Time Transfer Case
260 STARTING AND OPERATING
3. The transfer casewill notshift.
NOTE: Before retrying a selection, make certain that all
the necessary requirements for selecting a new transfer
case position have been met. To retry the selection, turn the
control switch back to the current position, wait five
seconds, and retry selection. To find the shift requirements,
refer to the Shifting Procedure for your transfer case,
located in this section.
The “SVC 4WD Warning Light” monitors the electronic
shift four-wheel drive system. If this light remains on after
engine start up or illuminates during driving, it means that
the four-wheel drive system is not functioning properly
and that service is required.
WARNING!
Always engage the parking brake when powering
down the vehicle if the “SVC 4WD Warning Light” is
illuminated. Not engaging the parking brake may
allow the vehicle to roll, which may cause personal
injury. NOTE:
Do not attempt to make a shift while only the front
or rear wheels are spinning, as this can cause damage to
driveline components.
When operating your vehicle in 4WD LOW, the engine
speed is approximately three times that of the 2WD or
4WD LOCK positions at a given road speed. Take care not
to overspeed the engine and do not exceed 25 mph
(40 km/h).
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.
6
STARTING AND OPERATING 263
Shifting Procedure
NOTE:
•If any of the requirements to select a new transfer case
position have not been met, the transfer case will not
shift. The position indicator light for the previous posi-
tion will remain ON and the newly selected position
indicator light will continue to flash until all the require-
ments for the selected position have been met. To retry a
shift: return the control switch back to the original
position, make certain all shift requirements have been
met, wait five seconds and try the shift again.
• If all the requirements to select a new transfer case
position have been met, the current position indicator
light will turn OFF, the selected position indicator light
will flash until the transfer case completes the shift.
When the shift is complete, the position indicator light
for the selected position will stop flashing and remain
ON.
2WD To 4WD LOCK
Rotate the 4WD control switch to the desired position.
Shifts between 2WD and 4WD LOCK can be done with the
vehicle stopped or in motion. With the vehicle in motion, the transfer case will engage/disengage faster if you mo-
mentarily release the accelerator pedal after turning the
control switch. If the vehicle is stopped, the ignition switch
must be in the ON position with the engine either running
or off. This shift cannot be completed if the ignition switch
is in the ACC position.
NOTE:
The four-wheel drive system will not allow shifts
between 2WD/4WD LOCK if the front and/or rear wheels
are spinning (no traction). In this situation, the selected
position indicator light will flash and the original position
indicator light will remain ON. At this time, reduce speed
and stop spinning the wheels to complete the shift.
2WD Or 4WD LOCK To 4WD LOW
NOTE: When shifting into or out of 4WD LOW some gear
noise may be heard. This noise is normal and is not
detrimental to the vehicle or occupants.
Shifting can be performed with the vehicle rolling 2 to
3 mph (3 to 5 km/h) or completely stopped. You can use
either of the following procedures:
Preferred Procedure
1. With the engine running, slow the vehicle to 2 to 3 mph (3 to 5 km/h).
264 STARTING AND OPERATING
2. Shift the transmission into NEUTRAL.
3. While still rolling, rotate the transfer case control switchto the desired position.
4. After the desired position indicator light is ON (not flashing), shift the transmission back into gear.
Alternate Procedure
1. Bring the vehicle to a complete stop.
2. With the ignition switch in the ON position and the engine running, shift the transmission into NEUTRAL.
3. Rotate the transfer case control switch to the desired position.
4. After the desired position indicator light is ON (not flashing), shift the transmission back into gear.
NOTE:
• If Steps 1 or 2 of either the Preferred or Alternate
Procedure are not satisfied prior to attempting the shift,
then the desired position indicator light will flash con-
tinuously while the original position indicator light is
ON, until all requirements have been met. •
The ignition switch must be in the ON position for a
shift to take place and for the position indicator lights to
be operable. If the ignition switch is not in the ON
position, the shift will not take place and no position
indicator lights will be on or flashing.
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 performs simi-
larly to a conventional differential. On slippery 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 mo-
mentary application of the parking brake may be necessary
to gain maximum traction.
6
STARTING AND OPERATING 265
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.
POWER TAKE OFF OPERATION — IF EQUIPPED
(CHASSIS CAB ONLY)
This vehicle when equipped with PTO Prep and the
AS66RC automatic six-speed, will allow for an aftermarket
upfit with a transmission driven PTO (power take off). The
customer will have the ability to operate the PTO in either
a “stationary” or “mobile” mode. The vehicles will be
factory set to the “stationary” mode. To select “mobile”
mode, you will need to enter the commercial vehicle menu
on the instrument cluster screen and select mobile PTO mode. Details of the PTO selection modes and further PTO
information is available at the Ram Truck Bodybuilders
web site:
www.rambodybuilder.com.
AS66RC Six-Speed Automatic Transmission Only
The PTO drive gear (part of the AS66RC) operates at torque
converter turbine speed. The turbine speed will be less
than engine speed when the torque converter clutch is not
engaged and will be same as engine speed when the torque
converter clutch is engaged.
Stationary Mode
To operate the PTO in this mode the vehicle must meet the
following conditions:
• Transmission in PARK position (vehicles equipped with
automatic transmission.)
• PTO switch has been activated.
• Parking brake applied (vehicles equipped with manual
transmission).
• Brake pedal must not be applied.
• Vehicle engine must be running.
• No vehicle, brake or clutch switch faults present.
266 STARTING AND OPERATING
•PTO must be correctly installed using the vehicle pro-
vided circuits.
The instrument cluster will display a PTO Onmessage for
five seconds if the above conditions are met. Otherwise, the
instrument cluster will display a message To Operate PTO
Shift To Park indicating what operator action should be
taken to engage the PTO mode.
The customer has the choice to operate the PTO by utilizing
the cruise control switches or by utilizing a remote control
(provided by the PTO supplier). To operate the feature
using the cruise control switches, the customer must first
activate the PTO switch which will turn on the PTO. In
order to increase or decrease the engine idle speed, to
optimize the PTO function, the “RESUME/ACCEL” and
“DECEL” cruise switches can be used respectively. To
disengage PTO operation and return to “standard vehicle
operation” simply toggle the PTO switch to the OFF
position.
The torque converter clutch (TCC) will automatically en-
gage at engine speeds above 1,200 RPM (engine speed) in
PTO stationary mode. Once engaged, the TCC will remain
applied and will not disengage until the engine speed falls
below 1,000 RPM. TCC engagement is desirable for certain
types of PTO applications (Automatic Transmission Only). To operate the PTO via a remote switch, the customer must
make sure the above conditions are met. It is vital for
proper operation that the PTO and remote have been
installed correctly, paying special attention to ensure the
vehicle provided wiring has been connected properly. This
is the responsibility of the installer of the PTO and
switches/remote system. It is the responsibility of the PTO
manufacturer to ensure that their electrical (switches and
remote) system is compatible with the vehicle’s electrical
architecture and software functionality.
NOTE:
Single set speed can be programmed via the PTO
menu on the instrument cluster display. Further details are
available at the Ram Truck Bodybuilders web site located
at rambodybuilder.com
Mobile Mode
To operate the PTO in this mode the vehicle must meet the
following conditions:
•Mobile mode is activated via the menu on the instru-
ment cluster display.
• (ON/OFF) switch has been activated.
• Vehicles with automatic transmission must be in PARK
or DRIVE.
6
STARTING AND OPERATING 267
•Parking brake must not be applied.
• Brake pedal must not be applied.
• No vehicle, brake or clutch switch faults present.
• Vehicle engine must be running.
• PTO must be correctly installed using the vehicle pro-
vided circuits.
The customer may choose to use the PTO while the vehicle
is moving. To do so, the PTO function must be activated
prior to taking the vehicle out of PARK. This is accom-
plished by activating the upfitter-provided PTO on/off
switch. At this point, the customer may place the vehicle in
a forward or reverse gear and have PTO operation once the
vehicle begins to move. To disengage PTO operation and
return to “standard vehicle operation” simply toggle the
on/off switch to the OFF position.
NOTE: For application specific information with respect
to PTO and pump requirements and additional vehicle
information (wiring schematics, preset idle values, engine
speed limits, and vehicle hardware and software require-
ments) please refer to the Body Builders Guide by access-
ing rambodybuilder.com and choosing the appropriate
links.POWER STEERING
Hydraulic Power Steering
The standard power steering system will give you good
vehicle response and increased ease of maneuverability in
tight spaces. The system will provide mechanical steering
capability if power assist is lost.
If for some reason the power assist is interrupted, it will
still be possible to steer your vehicle. Under these condi-
tions, you will observe a substantial increase in steering
effort, especially at very low vehicle speeds and during
parking maneuvers.
NOTE:
• Increased noise levels at the end of the steering wheel
travel are considered normal and do not indicate that
there is a problem with the power steering system.
• Upon initial start-up in cold weather, the power steering
pump may make noise for a short amount of time. This
is due to the cold, thick fluid in the steering system. This
noise should be considered normal, and it does not in
any way damage the steering system.
268 STARTING AND OPERATING