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When To Use TOW/HAUL Mode
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting oc-
curs, push the TOW/HAUL switch to activate TOW/
HAUL mode. This will improve performance and reduce
the potential for transmission overheating or failure due
to excessive shifting. When operating in TOW/HAUL
mode, transmission upshifts are delayed, and the trans-
mission will automatically downshift (for engine brak-
ing) when the throttle is closed and/or during steady
braking maneuvers.The “TOW/HAUL Indicator Light” will illuminate in the
instrument cluster to indicate that TOW/HAUL mode
has been activated. Pushing the switch a second time
restores normal operation. Normal operation is always
the default at engine start-up. If TOW/HAUL mode is
desired, the switch must be pushed each time the engine
is started.
TOW/HAUL Switch
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WARNING!
Do not use the “TOW/HAUL” feature when driving
in icy or slippery conditions. The increased engine
braking 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 possi-
bly resulting 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 automati-
cally 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 Overdrive.
•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
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Page 418 of 669

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 aftermar-
ket 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 commer-
cial vehicle menu on the EVIC/DID 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.comAS66RC 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:
•
Be in PARK position (vehicles equipped with auto-
matic transmission.)
• PTO switch has been activated.
• Parking brake applied (vehicles equipped with
manual transmission).
• Brake pedal must not be applied.
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•Vehicle engine must be running.
• No vehicle, brake or clutch switch faults present.
• PTO must be correctly installed using the vehicle
provided circuits.
The Electronic Vehicle Information Center (EVIC) or
Driver Information Display (DID) will display a PTO
On message for five seconds if the above conditions are
met. Otherwise, the EVIC/DID 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 oper-
ate 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
engage 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 desir-
able 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
5
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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 EVIC/DID screen. Further details are avail-
able at the Ram Truck Bodybuilders web site located
atwww.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 EVIC/
DID screen.
• (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
provided 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
accomplished 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 opera-
tion” simply toggle the on/off switch to the OFF position.
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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
instrument cluster will alert the driver that the vehicle is
in four-wheel drive and that the front and rear drive-
shafts 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. The front and rear
driveshaft speeds must be equal for the shift to take
place. Shifting while only the front or rear wheels are
spinning can cause damage to the transfer case.
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 tempera-
tures.
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CAUTION!
Do not use 4L (Low) range when operating the
vehicle on dry pavement. Driveline hardware dam-
age 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 you momentarily release the accelera-
tor pedal after completing the shift. Apply a constant
force when shifting the transfer case lever.
2H Or 4H To 4L
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 foot on brake, and
turn the engine OFF. Make 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
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3. When the shift is complete, the indicator light for theselected position will stop flashing and remain ON.
If One Or More Shift Conditions Are Not Met:
1. The indicator light for the current position will remain ON.
2. The newly selected position indicator light will con- tinue to flash.
3. The transfer case will 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 knob back to the current position, wait five
seconds, and retry selection. To find the shift require-
ments, 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 function-
ing 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 or5
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