2018 Ram 4500 Chassis Cab cooling

CAUTION!
Failure to follow these cautions can cause damage to
the heating elements:
•Use care when washing the inside of the rear win-
dow. Do not use abrasive window cleaners on the
interior surface of the window. Use a soft cloth and a
mild washing solution, wiping parallel to the heat-
ing elements. Labels can be peeled off after soaking
with warm water.
• Do not use scrapers, sharp instruments, or abrasive
window cleaners on the interior surface of the win-
dow.
• Keep all objects a safe distance from the window.
Climate Control Functions
A/C (Air Conditioning)
The Air Conditioning (A/C) button allows the operator to
manually activate or deactivate the air conditioning sys-
tem. When the air conditioning system is turned on, cool
dehumidified air will flow through the outlets into the
cabin. For improved fuel economy, press the A/C button to
turn off the air conditioning and manually adjust the
blower and airflow mode settings. Also, make sure to select
only Panel, Bi-Level, or Floor modes. NOTE:
•
If fog or mist appears on the windshield or side glass,
select Defrost mode, and increase blower speed if
needed.
• If your air conditioning performance seems lower than
expected, check the front of the A/C condenser (located
in front of the radiator), for an accumulation of dirt or
insects. Clean with a gentle water spray from the front of
the radiator and through the condenser.
MAX A/C
MAX A/C sets the control for maximum cooling perfor-
mance.
Press and release to toggle between MAX A/C and the
prior settings. The button illuminates when MAX A/C is
on.
In MAX A/C, the blower level and mode position can be
adjusted to desired user settings. Pressing other settings
will cause the MAX A/C operation to switch to the selected
setting and MAX A/C to exit.
Recirculation
When outside air contains smoke, odors, or high humidity,
or if rapid cooling is desired, you may wish to recirculate
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GETTING TO KNOW YOUR VEHICLE 95

Operating Tips
NOTE:Refer to the chart at the end of this section for
suggested control settings for various weather conditions.
Summer Operation
The engine cooling system must be protected with a
high-quality antifreeze coolant to provide proper corrosion
protection and to protect against engine overheating. OAT
coolant (conforming to MS.90032) is recommended.
Winter Operation
To ensure the best possible heater and defroster perfor-
mance, make sure the engine cooling system is functioning
properly and the proper amount, type, and concentration
of coolant is used. Use of the Air Recirculation mode
during Winter months is not recommended, because it may
cause window fogging.
Vacation/Storage
Before you store your vehicle, or keep it out of service (i.e.,
vacation) for two weeks or more, run the air conditioning
system at idle for about five minutes, in fresh air with the
blower setting on high. This will ensure adequate system
lubrication to minimize the possibility of compressor dam-
age when the system is started again.
Window Fogging
Vehicle windows tend to fog on the inside in mild, rainy,
and/or humid weather. To clear the windows, select De-
frost or Mix mode and increase the front blower speed. Do
not use the Recirculation mode without A/C for long
periods, as fogging may occur.
Outside Air Intake
Make sure the air intake, located directly in front of the
windshield, is free of obstructions, such as leaves. Leaves
collected in the air intake may reduce airflow, and if they
enter the plenum, they could plug the water drains. In
Winter months, make sure the air intake is clear of ice,
slush, and snow.
Cabin Air Filter
The climate control system filters out dust and pollen from
the air. Contact an authorized dealer to service your cabin
air filter, and to have it replaced when needed.
3
GETTING TO KNOW YOUR VEHICLE 97

3. Speedometer•Indicates vehicle speed.
4. Fuel Gauge •The pointer shows the level of fuel in the fuel tank
when the ignition is in the ON/RUN position.
•
The fuel pump symbol points to the side of the
vehicle where the fuel door is located.
5. Temperature Gauge
•The temperature gauge shows engine coolant tem-
perature. Any reading within the normal range indi-
cates that the engine cooling system is operating
satisfactorily.
• The gauge pointer will likely indicate a higher tem-
perature when driving in hot weather, up mountain
grades, or when towing a trailer. It should not be
allowed to exceed the upper limits of the normal
operating range.
WARNING!
A hot engine cooling system is dangerous. You or
others could be badly burned by steam or boiling
coolant. You may want to call an authorized dealer for
service if your vehicle overheats. If you decide to look
under the hood yourself, see “Servicing And Mainte-
nance.” Follow the warnings under the Cooling System
Pressure Cap paragraph.
CAUTION!
Driving with a hot engine cooling system could dam-
age your vehicle. If the temperature gauge reads “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 the
“H,” turn the engine off immediately and call an
authorized dealer for service.
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GETTING TO KNOW YOUR INSTRUMENT PANEL 131

pointer moves to either extreme left or right and
remains there during normal driving, the electrical
system should be serviced.
NOTE: The voltmeter may show a gauge fluctuation at
various engine temperatures. This cycling operation is
caused by the post-heat cycle of the intake manifold heater
system. The number of cycles and the length of the cycling
operation is controlled by the engine control module.
Post-heat operation can run for several minutes, and then
the electrical system and voltmeter needle will stabilize.
3. Oil Pressure Gauge
•The pointer should always indicate some oil pressure
when the engine is running. A continuous high or low
reading under normal driving conditions may indicate
a lubrication system malfunction. Immediate service
should be obtained from an authorized dealer.
4. Speedometer •Indicates vehicle speed.
5. Fuel Gauge •The pointer shows the level of fuel in the fuel tank
when the ignition is in the ON/RUN position. •The fuel pump symbol points to the side of the
vehicle where the fuel door is located.
6. Instrument Cluster Display
•When the appropriate conditions exist, this display
shows the instrument cluster display messages. Refer
to “Instrument Cluster Display” in “Getting To Know
Your Instrument Panel” for further information.
7. Temperature Gauge •The temperature gauge shows engine coolant tem-
perature. Any reading within the normal range indi-
cates that the engine cooling system is operating
satisfactorily.
• The gauge pointer will likely indicate a higher tem-
perature when driving in hot weather, up mountain
grades, or when towing a trailer. It should not be
allowed to exceed the upper limits of the normal
operating range.
WARNING!
A hot engine cooling system is dangerous. You or
others could be badly burned by steam or boiling
coolant. You may want to call an authorized dealer for
(Continued)
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GETTING TO KNOW YOUR INSTRUMENT PANEL 133

WARNING!(Continued)
service if your vehicle overheats. If you decide to look
under the hood yourself, see “Servicing And Mainte-
nance.” Follow the warnings under the Cooling System
Pressure Cap paragraph.
CAUTION!
Driving with a hot engine cooling system could dam-
age your vehicle. If the temperature gauge reads “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 the
“H,” turn the engine off immediately and call an
authorized dealer for service.
INSTRUMENT CLUSTER DISPLAY
Your vehicle may be equipped with an instrument cluster
display, which offers useful information to the driver. With
the ignition in the STOP/OFF mode, opening/closing of a
door will activate the display for viewing, and display the
total miles, or kilometers, in the odometer. Your instrument
cluster display is designed to display important informa-
tion about your vehicle’s systems and features. Using a
driver interactive display located on the instrument panel,
your instrument cluster display can show you how sys-
tems are working and give you warnings when they are
not. The steering wheel mounted controls allow you to
scroll through the main menus and submenus. You can
access the specific information you want and make selec-
tions and adjustments.
134 GETTING TO KNOW YOUR INSTRUMENT PANEL

Transporting Pets
Air Bags deploying in the front seat could harm your pet.
An unrestrained pet will be thrown about and possibly
injured, or injure a passenger during panic braking or in a
collision.
Pets should be restrained in the rear seat in pet harnesses or
pet carriers that are secured by seat belts.
SAFETY TIPS
Transporting Passengers
NEVER TRANSPORT PASSENGERS IN THE CARGO AREA.
WARNING!
•Do not leave children or animals inside parked
vehicles in hot weather. Interior heat build-up may
cause serious injury or death.
• It is extremely dangerous to ride in a cargo area,
inside or outside of a vehicle. In a collision, people
riding in these areas are more likely to be seriously
injured or killed.
• Do not allow people to ride in any area of your
vehicle that is not equipped with seats and seat belts.
(Continued)
WARNING! (Continued)
•Be sure everyone in your vehicle is in a seat and
using a seat belt properly.
Exhaust Gas
WARNING!
Exhaust gases can injure or kill. They contain carbon
monoxide (CO), which is colorless and odorless.
Breathing it can make you unconscious and can even-
tually poison you. To avoid breathing (CO), follow
these safety tips:
• Do not run the engine in a closed garage or in
confined areas any longer than needed to move your
vehicle in or out of the area.
• If you are required to drive with the trunk/liftgate/
rear doors open, make sure that all windows are
closed and the climate control BLOWER switch is set
at high speed. DO NOT use the recirculation mode.
• If it is necessary to sit in a parked vehicle with the
engine running, adjust your heating or cooling con-
trols to force outside air into the vehicle. Set the
blower at high speed.5
SAFETY 233

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 tempera-
ture as well as vehicle speed. This feature improves warm
up time of the engine and transmission to achieve maxi-
mum efficiency. Engagement of the torque converter clutch
is inhibited until the transmission fluid is warm (refer to
the “Note” under “Torque Converter Clutch” in this sec-
tion).
On models with 66RFE transmission, top overdrive gear is
also inhibited until the transmission fluid is warm, and
during extremely cold temperatures (-16°F [-27°C] or be-
low), operation may briefly be limited to first and direct
gears only. On trucks with AS66RC 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 re-
duced. 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 ab-
normal 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 fourth gear (for 66RFE transmission) or third gear (for
AS66RC transmission) regardless of which forward gear is
selected. If an AS66RC equipped truck enters 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. Limp Home Mode allows the vehicle to be
driven to an authorized dealer for service without damag-
ing 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.
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STARTING AND OPERATING 253

NOTE:Check the automatic transmission fluid level be-
fore towing.
Tow/Haul Mode
To reduce potential for automatic transmission overheat-
ing, activate TOW/HAUL mode when driving in hilly
areas, or select a lower gear range (using the Electronic
Range Select (ERS) shift control) on more severe grades.
Speed Control — If Equipped
• Do not use on hilly terrain or with heavy loads.
• When using the speed control, if you experience speed
drops greater than 10 mph (16 km/h), disengage until
you can get back to cruising speed.
• Use speed control in flat terrain and with light loads to
maximize fuel efficiency.
Cooling System
To reduce potential for engine and transmission overheat-
ing, take the following actions:
City Driving
In city traffic — while stopped, place the transmission in
NEUTRAL, but do not increase engine idle speed.
Highway Driving
Reduce speed.
Air Conditioning
Turn off temporarily.
Air Suspension System
To aid in attaching/detaching the trailer from the vehicle,
the air suspension system can be used. Refer to “Air
Suspension System” in “Starting And Operating” for fur-
ther information.
NOTE: The vehicle must remain in the engine running
position while attaching a trailer for proper leveling of the
air suspension system.
308 STARTING AND OPERATING