
NOTE:After selecting any gear range, wait a moment to
allow the selected gear to engage before accelerating.
This is especially important when the engine is cold.
PARK (P)
This range supplements the parking brake by locking the
transmission. The engine can be started in this range.
Never attempt to use PARK while the vehicle is in
motion. Apply the parking brake when leaving the
vehicle in this range.
When parking on a level surface, you may shift the
transmission into PARK first, and then apply the park-
ing brake.
When parking on a hill, apply the parking brake before
shifting the transmission to PARK, otherwise the load on
the transmission locking mechanism may make it difficultto move the shift lever out of PARK. As an added precau-
tion, turn the front wheels toward the curb on a downhill
grade and away from the curb on an uphill grade.
On four-wheel drive vehicles be sure that the transfer
case is in a drive position.
WARNING!
•Never use the PARK position as a substitute for the
parking brake. Always apply the parking brake
fully when parked to guard against vehicle move-
ment and possible injury or damage.
•Your vehicle could move and injure you and others
if it is not in PARK. Check by trying to move the
shift lever out of PARK with the brake pedal
released. Make sure the transmission is in PARK
before leaving the vehicle.
(Continued)
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STARTING AND OPERATING 229

NEUTRAL (N)
Use this range when the vehicle is standing for prolonged
periods with the engine running. The engine may be
started in this range. Apply the parking brake and shift
the transmission into PARK if you must leave the vehicle.
WARNING!
Do not coast in NEUTRAL and never turn off the
ignition to coast down a hill. These are unsafe
practices that limit your response to changing traffic
or road conditions. You might lose control of the
vehicle and have a collision.
CAUTION!
Towing the vehicle, coasting, or driving for any other
reason with the transmission in NEUTRAL can cause
(Continued)
CAUTION!(Continued)
severe transmission damage. Refer to “Recreational
Towing” in “Starting And Operating” and “Towing A
Disabled Vehicle” in “What To Do In Emergencies”
for further information.
DRIVE (D)
This range should be used for most city and highway
driving. It provides the smoothest upshifts and down-
shifts, and the best fuel economy. The transmission
automatically upshifts through underdrive first, second,
and third gears, direct fourth gear and overdrive fifth and
sixth gears. The DRIVE position provides optimum driv-
ing characteristics under all normal operating conditions.
232 STARTING AND OPERATING

The “TOW/HAUL Indicator Light” will illuminate in the
instrument cluster to indicate that TOW/HAUL mode
has been activated. Pressing 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 pressed each time the engine
is started.
WARNING!
Do not use the “TOW/HAUL” feature when driving
in icy or slippery conditions. The increased engine
braking could cause the rear wheels to slide, and the
vehicle to swing around with the possible loss of
vehicle control, which could 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.
TOW/HAUL Switch
238 STARTING AND OPERATING

NOTE:
•The torque converter clutch will not engage (and
68RFE-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 the 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 trans-
mission 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 con-
verter will refill within five seconds after starting the
engine.
MANUAL TRANSMISSION — IF EQUIPPED
WARNING!
You or others could be injured if you leave the
vehicle unattended without having the parking
brake fully applied. The parking brake should al-
ways be applied when the driver is not in the vehicle,
especially on an incline.
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STARTING AND OPERATING 239

•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
provided circuits.
The Electronic Vehicle Information Center (EVIC) will
display aPTO Onmessage for five seconds if the above
conditions are met. Otherwise, the EVIC will display a
messageTo Operate PTO Shift To Parkindicating 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
4
STARTING AND OPERATING 245

NOTE:For application specific information with respect
to PTO and pump requirements and additional vehicle
information (wiring schematics, preset idle values, en-
gine speed limits, and vehicle hardware and software
requirements) please refer to the Body Builders Guide by
accessingwww.rambodybuilder.comand choosing the
appropriate links.
Power Take Off — Aftermarket Installation
If you did not order the PTO (Power Take Off) Prep
Package from the factory and want to convert your
vehicle, refer to the Body Builder’s Guide at
www.rambodybuilder.comor contact the manufacturer
directly at (866) 205–4102 (toll free).
ENGINE RUNAWAY
Diesel engine runaway is a rare condition affecting diesel
engines, where the engine consumes its own lubrication
oil and runs at higher and higher RPM until it overspeedsto a point where it destroys itself due to either mechani-
cal failure or engine seizure through lack of lubrication.
WARNING!
In case of engine runaway due to flammable fumes
from fuel spills or turbocharger oil leaks being
sucked into the engine, do the following to help
avoid personal injury and/or vehicle damage:
1. Turn the ignition switch to the OFF position.
2. Using a CO2 or dry chemical type fire extinguisher,
direct the spray from the fire extinguisher into the
grille on the passenger side so that the spray enters
the engine air intake.
The inlet for the engine air intake is located behind
the passenger side headlamp and receives air
through the grille.
4
STARTING AND OPERATING 247

(antifreeze) solution. The use of lower quality water
will reduce the amount of corrosion protection in the
engine cooling system.
Please note that it is the owner’s responsibility to main-
tain the proper level of protection against freezing ac-
cording to the temperatures occurring in the area where
the vehicle is operated.
NOTE:
•Some vehicles require special tools to add coolant
properly. Failure to fill these systems properly could
lead to severe internal engine damage. If any coolant is
needed to be added to the system please contact your
local authorized dealer.
•
Mixing engine coolant (antifreeze) types is not recom-
mended and can result in cooling system damage. If
HOAT and OAT coolant are mixed in an emergency, have
a authorized dealer drain, flush, and refill with OAT
coolant (conforming to MS.90032) as soon as possible.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of engine
coolant (antifreeze), and to ensure that the engine coolant
(antifreeze) will return to the radiator from the coolant
expansion bottle.
The cap should be inspected and cleaned if there is any
accumulation of foreign material on the sealing surfaces.
WARNING!
•Do not open hot engine cooling system. Never add
engine coolant (antifreeze) when the engine is
overheated. Do not loosen or remove the cap to cool
an overheated engine. Heat causes pressure to
build up in the cooling system. To prevent scalding
or injury, do not remove the pressure cap while the
system is hot or under pressure.
(Continued)
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MAINTAINING YOUR VEHICLE 313