2019 RAM CHASSIS CAB Owners Manual

STARTING AND OPERATING 279
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, exces -
sive vehicle loading, or cold temperatures.
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 drivesh -
afts from the powertrain. To be used for flat towing behind
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).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.
CAUTION!
Do not use 4L (Low) range when operating the vehicle on
dry pavement. Driveline hardware damage can result. 5

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

STARTING AND OPERATING 283
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 instrument
cluster display.
• (ON/OFF) switch has been activated.
• Transmission must be in PARK or DRIVE.
• Parking brake must not be applied.
• Brake pedal must not be applied.
• No vehicle or brake 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 “stan -
dard 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 requirements) please
refer to the Body Builders Guide by accessing rambody -
builder.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 conditions, you
will observe a substantial increase in steering effort, espe -
cially at very low vehicle speeds and during parking maneu -
vers. 5

284 STARTING AND OPERATING
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.
Power Steering Fluid Check
Checking the power steering fluid level at a defined service
interval is not required. The fluid should only be checked if
a leak is suspected, abnormal noises are apparent, and/or
the system is not functioning as anticipated. Check fluid level when the engine is cold and off. Coordinate inspection
efforts through an authorized dealer.
If necessary, add fluid to restore to the proper indicated
level. With a clean cloth, wipe any spilled fluid from all
surfaces. Refer to “Fluids And Lubricants” in “Technical
Specifications” for further information.CAUTION!
Prolonged operation of the steering system at the end of
the steering wheel travel will increase the steering fluid
temperature and it should be avoided when possible.
Damage to the power steering pump may occur. WARNING!
Fluid level should be checked on a level surface and with
the engine off to prevent injury from moving parts and
to ensure accurate fluid level reading. Do not overfill.
Use only manufacturer's recommended power steering
fluid.
CAUTION!
Do not use chemical flushes in your power steering
system as the chemicals can damage your power steering
components. Such damage is not covered by the New
Vehicle Limited Warranty.

STARTING AND OPERATING 285
SPEED CONTROL
When engaged, the Speed Control takes over accelerator
operations at speeds greater than 20 mph (32 km/h).
The Speed Control buttons are located on the right side of the
steering wheel.
Speed Control Buttons NOTE:
In order to ensure proper operation, the Speed Control
System has been designed to shut down if multiple speed
control functions are operated at the same time. If this
occurs, the Speed Control System can be reactivated by
pushing the Speed Control On/Off button and resetting the
desired vehicle set speed.
To Activate
Push the On/Off button to activate the Speed Control. The
cruise indicator light in the instrument cluster display will
illuminate. To turn the system off, push the On/Off button a
second time. The cruise indicator light will turn off. The
system should be turned off when not in use.
1 — On/Off Button 3 — SET (-)
2 — RES (+) 4 — CANCEL WARNING!
Leaving the Speed Control system on when not in use is
dangerous. You could accidentally set the system or
cause it to go faster than you want. You could lose
control and have an accident. Always leave the system
off when you are not using it. 5

286 STARTING AND OPERATING
To Set A Desired Speed
Turn the Speed Control on. When the vehicle has reached the
desired speed, push the SET (-) button and release. Release
the accelerator and the vehicle will operate at the selected
speed.
NOTE:
The vehicle should be traveling at a steady speed and on
level ground before pushing the SET (-) button.
To Vary The Speed Setting
To Increase Speed
When the Speed Control is set, you can increase speed by
pushing the RES (+) button.
The driver’s preferred units can be selected through the
instrument panel settings if equipped. Refer to “Getting To
Know Your Instrument Panel” for more information. The
speed decrement shown is dependant on the chosen speed
unit of U.S. (mph) or Metric (km/h):
U.S. Speed (mph)
• Pushing the RES (+) button once will result in a 1 mph
increase in set speed. Each subsequent tap of the button
results in an increase of 1 mph. • If the button is continually pushed, the set speed will
continue to increase until the button is released, then the
new set speed will be established.
Metric Speed (km/h)
• Pushing the RES (+) button once will result in a 1 km/h
increase in set speed. Each subsequent tap of the button
results in an increase of 1 km/h.
• If the button is continually pushed, the set speed will
continue to increase until the button is released, then the
new set speed will be established.
To Decrease Speed
When the Speed Control is set, you can decrease speed by
pushing the SET (-) button.
The driver’s preferred units can be selected through the
instrument panel settings if equipped. Refer to “Getting To
Know Your Instrument Panel” for more information. The
speed decrement shown is dependant on the chosen speed
unit of U.S. (mph) or Metric (km/h):