engine overheat RAM CHASSIS CAB 2022 User Guide

STARTING AND OPERATING117
IDLE SHUTDOWN
This feature can be enabled so that the truck will
automatically shutdown when the truck has been
idling for a set period of time when the engine is at
operating temperature. Idle time can be set in
5 minute increments between 5 and 60 minutes.
See an authorized dealer to enable this feature.
NOTE:The idle shut down timer is disabled while the PTO
(Power Take-off) is active.
PROGRAMMABLE MAXIMUM VEHICLE
S
PEED
This feature allows the owner to set a maximum
vehicle speed for the vehicle. The 2500 and
3500 Series maximum vehicle speed can be set
between 40 mph to 87 mph (64 km/h to
140 km/h). The 4500/5500 Series maximum
vehicle speed can be set between 40 mph to
85 mph (64 km/h to 136 km/h). See an
authorized dealer to enable this feature.
NOTE:DO NOT set the maximum vehicle speed to a value
greater than what the vehicle tires are rated for.
OPERATING PRECAUTIONS
Avoid Overheating The Engine
The temperature of the engine coolant (antifreeze:
a mixture of 50% ethylene-glycol and 50% water)
must not exceed the normal range of the
temperature gauge 240°F (116°C) with a 21 psi
(145 kPa) coolant pressure cap.
Usually the engine coolant (antifreeze)
temperature indicated during operation will be to
the left of center in the normal range of the gauge.
Avoid Low Coolant Temperature Operation
Continual operation at low engine coolant
(antifreeze) temperature below the normal range
on the gauge 140°F (60°C) can be harmful to the
engine. Low engine coolant (antifreeze)
temperature can cause incomplete combustion
which allows carbon and varnish to form on piston
rings and injector nozzles. Also, the unburned fuel
can enter the crankcase, diluting the lubricating oil
and causing rapid wear to the engine.
COOLING SYSTEM TIPS
To reduce potential for engine and transmission
overheating in high ambient temperature
conditions, take the following actions:
City Driving — When stopped, shift the transmis -
sion into NEUTRAL and increase engine idle
speed.
Highway Driving — Reduce your speed.
Up Steep Hills — Select a lower transmission
gear.
Air Conditioning — Turn it off temporarily.
Do Not Operate The Engine With Low Oil
Pressure
When the engine is at normal operating
temperature, the minimum oil pressures required
are:
Idle 700 to 800 RPM 10 psi (69 kPa)Full speed and load 30 psi (207 kPa)
CAUTION!
If oil pressure falls to less than normal readings,
shut the engine off immediately. Failure to do so
could result in immediate and severe engine
damage.
4

22_DPF_OM_EN_USC_t.book Page 117

126STARTING AND OPERATING
You can switch between DRIVE and ERS mode at
any vehicle speed. When the transmission gear
selector is in DRIVE, the transmission will operate
automatically, shifting between all available gears.
Tapping the GEAR “–” switch (on the steering
wheel) will activate ERS mode, display the current
gear in the instrument cluster, and set that gear as
the top available gear. Once in ERS mode, tapping
the GEAR “–” or GEAR “+” switch will change the
top available gear.

ERS Control

To exit ERS mode, simply push and hold the
GEAR “+” switch until the gear limit display
disappears from the instrument cluster.
When to Use TOW/HAUL Mode
When driving in hilly areas, towing a trailer, carrying
a heavy load, etc., and frequent transmission
shifting occurs, 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.

TOW/HAUL Switch
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.
6-SPEED AUTOMATIC TRANSMISSION —
I
F EQUIPPED
Chassis Cab models may use either the AS66RC or
AS69RC transmission (which are equipped with a
Power Take-Off (PTO) access cover on the side of
the transmission case).
The transmission gear position display (located in
the instrument cluster) indicates the transmission
gear range. The gear selector is mounted on the
right side of the steering column. You must press
1 — GEAR “+” Switch
2 — GEAR “–” Switch
WARNING!
Do not downshift for additional engine braking
on a slippery surface. The drive wheels could
lose their grip and the vehicle could skid,
causing a collision or personal injury.
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 possibly resulting in personal
injury or death.

22_DPF_OM_EN_USC_t.book Page 126

STARTING AND OPERATING129
When frequent transmission shifting occurs (such
as when operating the vehicle under heavy loading
conditions, in hilly terrain, traveling into strong
head winds, or while towing a heavy trailer), select
TOW/HAUL mode or use the Electronic Range
Select (ERS) shift control to select a lower gear
range Úpage 130. Under these conditions, using
a lower gear range will improve performance and
extend transmission life by reducing excessive
shifting and heat buildup.
If the transmission temperature exceeds normal
operating limits, the powertrain controller will
modify the transmission shift schedule and expand
the range of torque converter clutch engagement.
This is done to prevent transmission damage due
to overheating.
If the transmission becomes extremely hot or is in
danger of overheating, the Transmission
Temperature Warning Light may illuminate and the
transmission may operate differently until the
transmission cools down.
NOTE:Use caution when operating a heavily loaded
vehicle at low speeds (such as towing a trailer up a
steep grade, or in stop-and-go traffic) during hot
weather. In these conditions, torque converter slip
can impose a significant additional heat load on
the cooling system. Downshifting the transmission
to the lowest possible gear (when climbing a grade), or shifting to NEUTRAL (when stopped in
heavy traffic) can help to reduce this excess heat
generation.
During cold temperatures, transmission operation
may be modified depending on engine and
transmission temperature as well as vehicle
speed. This feature improves warm-up time of the
engine and transmission to achieve maximum
efficiency. Engagement of the torque converter
clutch is inhibited until the transmission fluid is
warm Ú
page 131.
On trucks with AS66RC or AS69RC transmission,
FIFTH and SIXTH gears may be inhibited briefly on
cold starts below 41°F (5°C), and during very cold
temperatures (-4°F [-20°C] or below), operation
may briefly be limited to third gear only. During this
condition, the ability of the vehicle to accelerate
under heavily loaded conditions may be reduced.
In all cases, normal operation will resume once the
transmission temperature has risen to a suitable
level.Transmission Limp Home Mode
Transmission function is monitored electronically
for abnormal conditions. If a condition is detected
that could result in transmission damage,
Transmission Limp Home Mode is activated. In this
mode, the transmission remains in THIRD gear
regardless of which forward gear is selected. If an
AS66RC/AS69RC equipped truck enters
Transmission Limp Home Mode at highway speeds, it will initially engage FIFTH gear, until the
vehicle slows to a speed where THIRD gear can be
engaged. PARK, REVERSE, and NEUTRAL will
continue to operate. The Malfunction Indicator
Light (MIL) may be illuminated. Transmission Limp
Home Mode allows the vehicle to be driven to an
authorized dealer for service without damaging the
transmission.
In the event of a momentary problem, the
transmission can be reset to regain all forward
gears by performing the following steps:

1. Stop the vehicle.

2. Shift the transmission into PARK.
3. Turn the ignition to the OFF position.
4. Wait approximately 10 seconds.
5. Restart the engine.
6. Shift into the desired gear range. If the
problem is no longer detected, the
transmission will return to normal operation.
NOTE:Even if the transmission can be reset, we
recommend that you visit an authorized dealer at
your earliest possible convenience. An authorized
dealer has diagnostic equipment to assess the
condition of your transmission.
If the transmission cannot be reset, authorized
dealer service is required.
4

22_DPF_OM_EN_USC_t.book Page 129

STARTING AND OPERATING131
When To Use TOW/HAUL Mode
When driving in hilly areas, towing a trailer, carrying
a heavy load, etc., and frequent transmission
shifting occurs, 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
transmission will automatically downshift (for
engine braking) when the throttle is closed and/or
during steady braking maneuvers.

TOW/HAUL Switch

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.
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,
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 transmission 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.
AUXILIARY SWITCHES — IF EQUIPPED
There can be up to six auxiliary switches located in
the lower switch bank of the instrument panel
which can be used to power various electronic
devices and Power Take Off (PTO). If equipped, it
will take the place of the sixth auxiliary switch.
Connections to the switches are found under the
hood in the connectors attached to the auxiliary
Power Distribution Center.
You have the ability to configure the functionality of
the auxiliary switches via the instrument cluster
display. All switches can now be configured for
setting the switch type operation to latching or
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 possibly resulting in personal
injury or death.
4

22_DPF_OM_EN_USC_t.book Page 131

STARTING AND OPERATING147
When ACC Is Active
When you use the SET (-) button to decelerate, if
the engine’s braking power does not slow the
vehicle sufficiently to reach the set speed, the
brake system will automatically slow the
vehicle.
The ACC system applies the brake down to a full
stop when following the vehicle in front. If your
vehicle follows the vehicle in front to a standstill,
your vehicle will release the brakes two seconds
after coming to a full stop.
The ACC system maintains set speed when
driving uphill and downhill. However, a slight
speed change on moderate hills is normal. In
addition, downshifting may occur while climbing
uphill or descending downhill. This is normal
operation and necessary to maintain set speed.
When driving uphill and downhill, the ACC
system will cancel if the braking temperature
exceeds normal range (overheated).
Setting The Following Distance In ACC
The specified following distance for Adaptive
Cruise Control (ACC) can be set by varying the
distance setting between four bars (longest), three
bars (long), two bars (medium) and one bar (short).
Using this distance setting and the vehicle speed,
ACC calculates and sets the distance to the vehicle
ahead. This distance setting displays in the
instrument cluster display.
Distance Settings

To adjust the distance setting, push the Distance
Button and release. Each time the button is
pushed, the distance setting increases by one bar
(longer). When the farthest distance is set, pushing
the distance button again will reset to the shortest
distance.
If there is no vehicle ahead, the vehicle will
maintain the set speed. If a slower moving vehicle
is detected in the same lane, the instrument
cluster displays the ACC Set With Target Detected
Indicator Light, and the system adjusts vehicle
speed automatically to maintain the distance
setting, regardless of the set speed. The vehicle will then maintain the set distance
until:
The vehicle ahead accelerates to a speed above
the set speed.
The vehicle ahead moves out of your lane or
view of the sensor.
The distance setting is changed.
The system disengages.
The maximum braking applied by ACC is limited;
however, the driver can always apply the brakes
manually, if necessary.
NOTE:The brake lights will illuminate whenever the ACC
system applies the brakes.
A Proximity Warning will alert the driver if ACC
predicts that its maximum braking level is not
sufficient to maintain the set distance. If this
occurs, a visual alert “BRAKE!” will flash in the
instrument cluster display and a chime will sound
while ACC continues to apply its maximum braking
force.
NOTE:The “BRAKE!” screen in the instrument cluster
display is a warning for the driver to take action
and does not necessarily mean that the Forward
Collision Warning system is applying the brakes
autonomously.
1 — Longest Distance Setting (Four Bars)
2 — Medium Distance Setting (Two Bars)
3 — Long Distance Setting (Three Bars)
4 — Short Distance Setting (One Bar)
4

22_DPF_OM_EN_USC_t.book Page 147

182STARTING AND OPERATING
When activated the feature will enable all of the
exterior lights sequentially for up to five minutes
allowing time to walk around and verify
functionality. The following exterior lights will
remain on for the entirety of the sequence:
Park/Running Lamps
Side Marker Lamps (if equipped)
License Lamp
Signature Lamp (if equipped)
Low Beams
Fog Lamps (if equipped)
Daytime Running Lamps
During this time the following lights will sequence,
each activating for three seconds:

1. Brake and CHMSL (third brake light)

2. Left turn signal
3. Right turn signal
4. Reverse Lamps
5. High Beam
This light check sequence will continue for a total
of five minutes. The sequence will only activate if the following
conditions are met:
Vehicle is equipped with the Trailer Tow
Package
Vehicle is in PARK
Vehicle is not in motion
Ignition in ACC or RUN
Remote start is inactive
Brakes are not applied
Left turn signal is not applied
Right turn signal not applied
Hazard switch is not applied
The sequence will cancel if any of the following
conditions occur:
Brakes are applied
Vehicle is shifted from PARK
Vehicle is no longer stationary
Left turn signal activated from stalk
Right turn signal is activated from stalk
Hazard switch is activated
Any button on the key fob is pushed
Ignition button is pushed
High Beam stalk position is changed
Sequence is canceled in the instrument cluster
TOWING TIPS
Before setting out on a trip, practice turning,
stopping, and backing up the trailer in an area
located away from heavy traffic.
Automatic Transmission
The DRIVE range can be selected when towing. The
transmission controls include a drive strategy to
avoid frequent shifting when towing. However, if
frequent shifting does occur while in DRIVE, select
TOW/HAUL mode or select a lower gear range
(using the Electronic Range Select (ERS) shift
control).
NOTE:Using TOW/HAUL mode or selecting a lower gear
range (using the ERS shift control) while operating
the vehicle under heavy loading conditions will
improve performance and extend transmission life
by reducing excessive shifting and heat build-up.
This action will also provide better engine braking.
6-Speed Automatic Transmission Only
When towing a loaded trailer up steep grades at
low speeds (20 mph [32 km/h] or below), holding
your vehicle in FIRST gear (using the ERS shift
control) can help to avoid transmission
overheating.

22_DPF_OM_EN_USC_t.book Page 182

184STARTING AND OPERATING
The loaded vehicle weight, including the snowplow
system, all aftermarket accessories, driver,
passengers, options, and cargo, must not exceed
either the Gross Vehicle Weight Rating (GVWR) or
Gross Axle Weight Rating (GAWR). These weights
are specified on the Safety Compliance
Certification Label on the driver's side door
opening.
NOTE:Detach the snowplow when transporting
passengers.
Vehicle front end wheel alignment was set to
specifications at the factory without consideration
for the weight of the plow. Front end toe-in should
be checked and reset if necessary at the beginning
and end of the snowplow season. This will help
prevent uneven tire wear.
The blade should be lowered whenever the vehicle
is parked.
Maintain and operate your vehicle and snowplow
equipment following the recommendations
provided by the specific snowplow manufacturer.
OVER THE ROAD OPERATION WITH
S
NOWPLOW ATTACHED
The blade restricts air flow to the radiator and
causes the engine to operate at higher than
normal temperatures. Therefore, when
transporting the plow, angle the blade completely
and position it as low as road or surface conditions
permit. Do not exceed 40 mph (64 km/h). The
operator should always maintain a safe stopping
distance and allow adequate passing clearance.
OPERATING TIPS
Under ideal snow plowing conditions, 20 mph
(32 km/h) should be maximum operating speed.
The operator should be familiar with the area and
surface to be cleaned. Reduce speed and use
extreme caution when plowing unfamiliar areas or
under poor visibility.
GENERAL MAINTENANCE
Snowplows should be maintained in accordance
with the plow manufacturer's instructions.
Keep all snowplow electrical connections and
battery terminals clean and free of corrosion.
When plowing snow, to avoid transmission and
drivetrain damage, the following precautions
should be observed.
Operate with transfer case in 4WD LOW when
plowing small or congested areas where speeds
are not likely to exceed 15 mph (24 km/h). At
higher speeds operate in 4WD HIGH.
Vehicles with automatic transmissions should
use 4WD LOW when plowing deep or heavy
snow for extended periods of time to avoid
transmission overheating.
Do not shift the transmission unless the engine
has returned to idle and wheels have stopped.
Make a practice of stepping on the brake pedal
while shifting the transmission.

22_DPF_OM_EN_USC_t.book Page 184

322IN CASE OF EMERGENCY
IF YOUR ENGINE OVERHEATS
In any of the following situations, you can reduce
the potential for overheating by taking the
appropriate action.
On the highways — slow down.
In city traffic — while stopped, place the trans -
mission in NEUTRAL, but do not increase the
engine idle speed while preventing vehicle
motion with the brakes.
NOTE:There are steps that you can take to slow down an
impending overheat condition:
If your Air Conditioner (A/C) is on, turn it off. The
A/C system adds heat to the engine cooling
system and turning the A/C off can help remove
this heat.
You can also turn the temperature control to
maximum heat, the mode control to floor and
the blower control to high. This allows the heater
core to act as a supplement to the radiator and
aids in removing heat from the engine cooling
system.
GEAR SELECTOR OVERRIDE
6–SPEED TRANSMISSION
In order to move the vehicle in cases where the
transmission will not shift out of PARK (P) (such as
a depleted battery), a Manual Park Release is
available.

1. Turn the engine OFF.

2. Firmly apply the parking brake.
3. Tilt the steering wheel to the full up position.
4. Press and maintain firm pressure on the brake pedal.
5. Insert a screwdriver or similar tool into the access port (ringed circle) on the bottom of the
steering column, and push and hold the
override release lever up.

Gear Selector Override Access Port Location

WARNING!
You or others can be badly burned by hot engine
coolant (antifreeze) or steam from your radiator.
If you see or hear steam coming from under the
hood, do not open the hood until the radiator
has had time to cool. Never try to open a cooling
system pressure cap when the radiator or cool -
ant bottle is hot.
CAUTION!
Driving with a hot cooling system could damage
your vehicle. If the temperature gauge reads
HOT (H), pull over and stop the vehicle. Idle the
vehicle with the air conditioner turned off until
the pointer drops back into the normal range. If
the pointer remains on HOT (H), and you hear
continuous chimes, turn the engine off immedi -
ately and call for service.

22_DPF_OM_EN_USC_t.book Page 322

IN CASE OF EMERGENCY325
TOWING A DISABLED VEHICLE
This section describes procedures for towing a disabled vehicle using a commercial towing service. If the transmission and drivetrain are operable, disabled
vehicles may also be towed as described Ú page 185.
CAUTION!
Racing the engine or spinning the wheels may lead to transmission overheating and failure. Allow the engine to idle with the transmission in NEUTRAL for
at least one minute after every five rocking-motion cycles. This will minimize overheating and reduce the risk of transmission failure during prolonged efforts
to free a stuck vehicle.
When “rocking” a stuck vehicle by shifting between DRIVE and REVERSE, do not spin the wheels faster than 15 mph (24 km/h), or drivetrain damage may
result.
Revving the engine or spinning the wheels too fast may lead to transmission overheating and failure. It can also damage the tires. Do not spin the wheels
above 30 mph (48 km/h) while in gear (no transmission shifting occurring).
Towing ConditionWheels OFF The
Ground 2WD Models
4WD Models
Flat Tow NONEIf transmission is operable:

Transmission in NEUTRAL
30 mph (48 km/h) max speed
15 miles (24 km) max distance (6–speed transmission)
30 miles (48 km) max distance (8–speed transmission) Detailed instructions
Úpage 185
Auto Transmission in PARK
Transfer Case in NEUTRAL
Tow in forward direction
Wheel Lift Or Dolly Tow Front
NOT ALLOWED
Rear OK NOT ALLOWED
Flatbed ALL BEST METHOD BEST METHOD
7

22_DPF_OM_EN_USC_t.book Page 325

354SERVICING AND MAINTENANCE
(Continued)
(Continued) Under normal operating conditions, the catalytic
converter will not require maintenance. However, it
is important to keep the engine properly tuned to
ensure proper catalyst operation and prevent
possible catalyst damage.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being
assessed against you.
In unusual situations involving grossly
malfunctioning engine operation, a scorching odor
may suggest severe and abnormal catalyst
overheating. If this occurs, stop the vehicle, turn off
the engine and allow it to cool. Service, including a
tune-up to manufacturer's specifications, should
be obtained immediately. To minimize the possibility of catalytic converter
damage:
Do not interrupt the ignition when the transmis
-
sion is in gear and the vehicle is in motion.
Do not try to start the vehicle by pushing or
towing the vehicle.
Do not idle the engine with any ignition compo -
nents disconnected or removed, such as when
diagnostic testing, or for prolonged periods
during very rough idle or malfunctioning oper -
ating conditions.
COOLING SYSTEM
WARNING!
Exhaust gases can injure or kill. They contain
carbon monoxide (CO), which is colorless and
odorless. Breathing it can make you uncon -
scious and can eventually poison you
Ú page 309.
A hot exhaust system can start a fire if you
park over materials that can burn. Such mate -
rials might be grass or leaves coming into
contact with your exhaust system. Do not park
or operate your vehicle in areas where your
exhaust system can contact anything that can
burn.
CAUTION!
The catalytic converter requires the use of
unleaded fuel only. Leaded gasoline will
destroy the effectiveness of the catalyst as an
emissions control device and may seriously
reduce engine performance and cause
serious damage to the engine.
Damage to the catalytic converter can result if
your vehicle is not kept in proper operating
condition. In the event of engine malfunction,
particularly involving engine misfire or other
apparent loss of performance, have your
vehicle serviced promptly. Continued opera -
tion of your vehicle with a severe malfunction
could cause the converter to overheat,
resulting in possible damage to the converter
and vehicle.
CAUTION!
WARNING!
You or others can be badly burned by hot
engine coolant (antifreeze) or steam from your
radiator. If you see or hear steam coming from
under the hood, do not open the hood until the
radiator has had time to cool. Never open a
cooling system pressure cap when the radi -
ator or coolant bottle is hot.
Keep hands, tools, clothing, and jewelry away
from the radiator cooling fan when the hood is
raised. The fan starts automatically and may
start at any time, whether the engine is
running or not.

22_DPF_OM_EN_USC_t.book Page 354