Page 337 of 534

WARNING!
Do not use the “TOW/HAUL” feature when driving in
icy or slippery conditions. The increased engine brak-
ing can cause the rear wheels to slide, and the vehicle
to swing around with the possible loss of vehicle
control, which may cause an accident possibly result-
ing in personal injury or death.
Torque Converter Clutch
A feature designed to improve fuel economy has been
included in the automatic transmission on your vehicle. A
clutch within the torque converter engages automatically
at calibrated speeds. This may result in a slightly different
feeling or response during normal operation in the upper
gears. When the vehicle speed drops or during some
accelerations, the clutch automatically disengages.NOTE:
•
The torque converter clutch will not engage (and 66RFE-
equipped trucks will not shift to sixth gear), until the
transmission fluid and engine coolant are warm [usually
after 1 to 3 miles (2 to 5 km) of driving]. Because engine
speed is higher when the torque converter clutch is not
engaged, it may seem as if the transmission is not
shifting properly when cold. This is normal. Using the
Electronic Range Select (ERS) shift control, when the
transmission is sufficiently warm, will demonstrate that
the transmission is able to shift into and out of Over-
drive.
• If the vehicle has not been driven for several days, the
first few seconds of operation after shifting the transmis-
sion into gear may seem sluggish. This is due to the fluid
partially draining from the torque converter into the
transmission. This condition is normal and will not
cause damage to the transmission. The torque converter
will refill within five seconds after starting the engine.
5
STARTING AND OPERATING 335
Page 338 of 534

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.
• 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
336 STARTING AND OPERATING
Page 339 of 534

“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.comMobile 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.
• 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
5
STARTING AND OPERATING 337
Page 340 of 534

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.
FOUR-WHEEL DRIVE OPERATION — IF EQUIPPED
Four-wheel drive trucks are equipped with either a manu-
ally shifted transfer case or an electronically shifted trans-
fer case. Refer to the operating instructions for your
transfer case, located in this section for further information.
Manually Shifted Transfer Case — If Equipped
The transfer case provides four mode positions:
• Two-Wheel Drive High Range (2H)
• Four-Wheel Drive Lock High Range (4H)
• Neutral (N)
• Four-Wheel Drive Low Range (4L) For additional information on the appropriate use of each
transfer case mode position, see the information below:
2H
Two-Wheel Drive High Range — This range is for normal
street and highway driving on dry, hard surfaced roads.
4H
Four-Wheel Drive Lock High 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.
NEUTRAL (N)
Neutral — This range disengages both the front and rear
driveshafts from the powertrain. To be used for flat towing
behind another vehicle. Refer to “Recreational Towing” in
“Starting And Operating” for further information.
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).
338 STARTING AND OPERATING
Page 341 of 534

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 in
four-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.
5
STARTING AND OPERATING 339
Page 342 of 534

WARNING!
You or others could be injured or killed if you leave the
vehicle unattended with the transfer case in the NEU-
TRAL position without first fully engaging the park-
ing brake. The transfer case NEUTRAL position disen-
gages 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.
Two-Wheel Drive High Range (2H)
Rear-Wheel Drive High Range — This range is for normal
street and highway driving on dry hard surfaced roads.
Four-Wheel Drive High Range (4H)
Four-Wheel Drive High 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.
Neutral (N)
Neutral — This range disengages the front and rear
driveshafts from the powertrain. To be used for flat towingbehind another vehicle. Refer to “Recreational Towing” in
“Starting And Operating” for further information.
Four-Wheel Drive Low Range (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).
CAUTION!
Do not use 4L (Low) range when operating the vehicle
on dry pavement. Driveline hardware damage can
result.
Shifting Procedure — Manually Shifted Transfer
Case
2H To 4H
Shifting between 2H and 4H can be made with the vehicle
stopped or in motion. If the vehicle is in motion, shifts can
be made up to 55 mph (88 km/h). With the vehicle in
motion, the transfer case will engage/disengage faster if
340 STARTING AND OPERATING
Page 343 of 534

you momentarily release the accelerator pedal after com-
pleting the shift. Apply a constant force when shifting the
transfer case lever.
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 align-
ment 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.
5
STARTING AND OPERATING 341
Page 344 of 534

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.
This electronically shifted transfer case provides four mode
positions:
•Two-Wheel Drive High Range (2WD)
• Four-Wheel Drive Lock High Range (4WD LOCK) •
Four-Wheel Drive Low Range (4WD LOW)
• Neutral (NEUTRAL)
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 LOCK
Four-Wheel Drive Lock High Range — This range maxi-
mizes torque to the front driveshaft, forcing the front and
rear wheels to rotate at the same speed. This range pro-
vides 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).
Four-Position/Part Time Transfer Case
342 STARTING AND OPERATING