engine overheat RAM CHASSIS CAB 2021 User Guide

134STARTING AND OPERATING
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 trans
-
mission 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.

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146STARTING AND OPERATING

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.

SIX-SPEED AUTOMATIC
T
RANSMISSION — IF 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 the brake pedal to move the gear
selector out of PARK
Ú
page 141. Pull the gear
selector toward you when shifting into REVERSE
or PARK, or when shifting out of PARK.

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.

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STARTING AND OPERATING149
REVERSE (R)
This range is for moving the vehicle backward.
Shift into REVERSE only after the vehicle has
come to a complete stop.
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 exit the vehicle. DRIVE (D)
This range should be used for most city and
highway driving. It provides the smoothest
upshifts and downshifts, and the best fuel
economy. The transmission automatically
upshifts through all forward gears.
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 150. 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 addi
-
tional heat load on the cooling system. Down -
shifting 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 151.
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 severe transmission damage.

For Towing A Disabled Vehicle Ú page 350.
For Recreational Towing Ú page 215.
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152STARTING AND OPERATING
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.
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.
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
momentary, power source of either battery or
ignition, and ability to hold last state across key
cycles.

NOTE:
Holding last state conditions are met when
switch type is set to latching and power source
is set to ignition.

For further information on using the auxiliary
switches, please refer to the Ram Body Builders
Guide by accessing
https://www.ramtrucks.com/
ram-commercial/body-builders-guide.html
and
choosing the appropriate links.

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.

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STARTING AND OPERATING211
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.
Six-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.
If you regularly tow a trailer for more than
45 minutes of continuous operation, then
change the automatic transmission fluid and
filter(s) as specified for "police, taxi, fleet, or
frequent trailer towing." Ú
page 354.
NOTE:
Check the automatic transmission fluid level
before towing (Six-speed automatic only).
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STARTING AND OPERATING213
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 4L 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 range 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.
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346IN CASE OF EMERGENCY
6. Once the engine is started, follow the
disconnecting procedure below.
Disconnecting The Jumper Cables

1. Disconnect the negative
(-)
end of the
jumper cable from the engine ground of
the vehicle with the discharged battery.

2. Disconnect the opposite end of the negative (-) jumper cable from the
negative (-) post of the booster battery.
3. Disconnect the positive (+) end of the
jumper cable from the positive (+) post of
the booster battery.
4. Disconnect the opposite end of the positive (+) jumper cable from the
positive (+) post of the vehicle with the
discharged battery.
If frequent jump starting is required to start your
vehicle you should have the battery and charging
system inspected at an authorized dealer.

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.
CAUTION!
Do not connect jumper cable to any of the
fuses on the positive battery terminal. The
resulting electrical current will blow the fuse.
CAUTION!

Accessories plugged into the vehicle power
outlets draw power from the vehicle’s battery,
even when not in use (i.e., cellular devices,
etc.). Eventually, if plugged in long enough
without engine operation, the vehicle’s battery
will discharge sufficiently to degrade battery
life and/or prevent the engine from starting.

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 coolant bottle is hot.

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IN CASE OF EMERGENCY349
To Reset The Manual Park Release:

1. Push the locking tab to the right, to unlock
the lever.

2. Rotate the Manual Park Release lever forward to its original position, until the
locking tab snaps into place to secure the
lever.
3. Pull gently on the tether strap to confirm that the lever is locked in its stowed
position.
4. Re-install the access cover.
FREEING A STUCK VEHICLE

If your vehicle becomes stuck in mud, sand, or
snow, it can often be moved using a rocking
motion. Turn the steering wheel right and left to
clear the area around the front wheels. Then shift
back and forth between DRIVE (D) and REVERSE
(R), while gently pressing the accelerator. Use the
least amount of accelerator pedal pressure that
will maintain the rocking motion, without
spinning the wheels or racing the engine.
NOTE:
For trucks equipped with an 8–speed trans
-
mission, shifts between DRIVE and REVERSE
can only be achieved at wheel speeds of
5 mph (8 km/h) or less. Whenever the trans -
mission remains in NEUTRAL (N) for more
than two seconds, you must press the brake
pedal to engage DRIVE or REVERSE.

Push the ESC OFF switch, to place the
Electronic Stability Control (ESC) system in
“Partial Off” mode, before rocking the vehicle

Ú
page 274. Once the vehicle has been freed,
push the ESC OFF switch again to restore ESC
On mode.

WARNING!

Fast spinning tires can be dangerous. Forces
generated by excessive wheel speeds may
cause damage, or even failure, of the axle and
tires. A tire could explode and injure someone.
Do not spin your vehicle's wheels faster than
30 mph (48 km/h) or for longer than
30 seconds continuously without stopping
when you are stuck and do not let anyone near
a spinning wheel, no matter what the speed.

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 over -
heating 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).
7

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SERVICING AND MAINTENANCE383

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 trans
-
mission 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
components disconnected or removed, such
as when diagnostic testing, or for prolonged
periods during very rough idle or malfunc -
tioning operating conditions.
COOLING SYSTEM 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 seri -
ously 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 malfunc -
tion, particularly involving engine misfire or
other apparent loss of performance, have
your vehicle serviced promptly. Continued
operation of your vehicle with a severe
malfunction could cause the converter to
overheat, resulting in possible damage to
the converter and vehicle.

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 radiator
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 automati -
cally and may start at any time, whether the
engine is running or not.
When working near the radiator cooling fan,
disconnect the fan motor lead or turn the
ignition to the OFF mode. The fan is
temperature controlled and can start at any
time the ignition is in the ON mode.
8

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SERVICING AND MAINTENANCE385
Please review these recommendations for
using Organic Additive Technology (OAT) engine
coolant that meets the requirements of FCA
Material Standard MS.90032. When adding
engine coolant:

We recommend using Mopar Antifreeze/
Coolant 10 Year/150,000 Mile (240,000 km)
Formula OAT that meets the requirements of
FCA Material Standard MS.90032.

Mix a minimum solution of 50% OAT engine
coolant that meets the requirements of FCA
Material Standard MS.90032 and distilled
water. Use higher concentrations (not to
exceed 70%) if temperatures below −34°F
(−37°C) are anticipated. Please contact an
authorized dealer for assistance.
Use only high purity water such as distilled or
deionized water when mixing the water/
engine coolant solution. The use of lower
quality water will reduce the amount of corro -
sion protection in the engine cooling system.
NOTE:
It is the owner's responsibility to maintain the
proper level of protection against freezing
according to the temperatures occurring in
the area where the vehicle is operated.
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 a local autho -
rized dealer.
Mixing engine coolant types is not recom -
mended and can result in cooling system
damage. If HOAT and OAT coolant are mixed
in an emergency, have an 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 engine coolant will return to the radiator
from the coolant expansion bottle/recovery
tank (if equipped).
The cap should be inspected and cleaned if
there is any accumulation of foreign material on
the sealing surfaces.Disposal Of Used Coolant
Used ethylene glycol-based coolant (antifreeze)
is a regulated substance requiring proper
disposal. Check with your local authorities
to determine the disposal rules for your
community. To prevent ingestion by animals or
children, do not store ethylene glycol-based
coolant in open containers or allow it to remain
in puddles on the ground, clean up any ground
spills immediately. If ingested by a child or pet,
seek emergency assistance immediately.
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.
Do not use a pressure cap other than the
one specified for your vehicle. Personal
injury or engine damage may result.
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