2019 RAM CHASSIS CAB engine

272 STARTING AND OPERATING
FOUR-WHEEL DRIVE OPERATION — IF EQUIPPED
Four-wheel drive trucks are equipped with either a manu -
ally shifted transfer case or an electronically shifted transfer
case. Refer to the operating instructions for your transfer
case, located in this section for further information. Four-Position Electronically Shifted Transfer Case —
If Equipped
This is an electronic shift transfer case and is operated by the
4WD Control Switch (Transfer Case Switch), which is
located on the instrument panel.
Four-Position Transfer CaseWARNING!
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 possibly resulting in
personal injury or death.

STARTING AND OPERATING 275
3. When the shift is complete, the indicator light for the
selected position will stop flashing and remain ON.
If One Or More Of The Following Shift Conditions Are
Not Met:
1. The indicator light for the current position will remain
ON.
2. The newly selected position indicator light will continue
to flash.
3. The transfer case will not shift.
NOTE:
Before retrying a selection, make certain that all the neces -
sary requirements for selecting a new transfer case position
have been met. To retry the selection, push the current posi -
tion, 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. NOTE:
Do not attempt to make a shift while only the front or rear
wheels are spinning. This could 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
HIGH positions at a given road speed. Take care not to over -
speed 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 drive -
train.
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. 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 or
death.
5

276 STARTING AND OPERATING
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 position will
remain ON and the newly selected position indicator light
will continue to flash until all the requirements for the
selected position have been met.
• 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 posi -
tion will stop flashing and remain ON.
2WD To 4WD HIGH
Push the desired position on the 4WD control switch to shift
the transfercase. Shifts between 2WD and 4WD HIGH can be
done with the vehicle stopped or in motion. With the vehicle
in motion, the transfer case will engage/disengage faster if
you momentarily 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 HIGH if the front and/or rear wheels are spin -
ning (no traction). In this situation, the selected position indi -
cator light will flash and the original position indicator light
will remain ON. At this time, reduce speed and stop spin -
ning the wheels to complete the shift.
2WD Or 4WD HIGH 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).
2. Shift the transmission into NEUTRAL.
3. While still rolling, push the desired position on the
transfer case control switch.

STARTING AND OPERATING 277
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. Push the desired position on the transfer case control
switch.
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 Proce -
dure are not satisfied prior to attempting the shift, then the
desired position indicator light will flash continuously
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. 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. 5

278 STARTING AND OPERATING
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).
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 posi -
tions 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.

280 STARTING AND OPERATING
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 accelerator pedal after completing
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 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 transmis -
sion 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.

STARTING AND OPERATING 281
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 slip -
pery 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 appli -
cation of the parking brake may be necessary to gain
maximum traction. 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 side -
ways 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 instru -
ment 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.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. 5

282 STARTING AND OPERATING
Stationary Mode
To operate the PTO in this mode the vehicle must meet the
following conditions:
• Transmission in PARK position.
• PTO switch has been activated.
• Brake pedal must not be applied.
• Vehicle engine must be running.
• No vehicle, or brake faults present.
• PTO must be correctly installed using the vehicle provided
circuits.
The instrument cluster will display a "PTO On" message 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 opera -
tion 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 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 manufac -
turer 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 rambody -
builder.com