2020 Ram 3500 air condition

STARTING AND OPERATING227
DECEL switch and the idle speed will
decrease to approximately 1,100 RPM.
3. To cancel the Idle–Up feature, either push the CANCEL switch, push the ON/OFF
switch, or press the brake pedal.

NOISE
Diesel engines can create noises that may seem
concerning. The nature of a diesel engine is
compression ignition where compressed air and
fuel are mixed and ignited. Weather, barometric
pressure, altitude, and temperature will affect how
fuel is ignited in the engine. Engines will sound
different from day to day or previous model years.
Clicking, ticking, or light knocking is normal and will
change from day to day, as the engine breaks in, and can vary with changes in ambient
temperature. Clicking sound from under the hood
shortly after vehicle shutdown is normal as
actuators such as the EGR valve are cycled. Fuel
pump noise may increase during low speed/light
load conditions when ambient temperature is
above 100°F (38°C), and when fuel tank level is
below 10% which is a normal condition of the fuel
system and controls strategy. Diesel equipped
vehicles also have an exhaust after-treatment
system to reduce emissions utilizing a DPF (refer to
“Odor” in this section for further information) and a
Selective Reduction Catalyst (SCR). The SCR
reduces Nitrogen Oxides (NOx) using the Diesel
Exhaust Fluid (DEF) system. DEF is injected directly
into the SCR through a dosing module. This
process will create a clicking sound and at times, will make noise even with the vehicle shut off. This
is normal as the DEF dosing module is purging
DEF. If at any time the check engine light is on,
please visit an authorized dealer.

STOPPING THE ENGINE
Idle the engine a few minutes before routine
shutdown. After full load operation, idle the
engine three to five minutes before shutting it
down. This idle period will allow the lubricating
oil and coolant to carry excess heat away from
the combustion chamber, bearings, internal
components, and turbocharger. This is
especially important for turbocharged, charge
air-cooled engines. Refer to the following chart
for proper engine shutdown:
Driving Condition
Load Turbocharger Temperature Idle Time (min.) Before Engine
Shutdown
Stop and Go EmptyCoolLess than One
Stop and Go Medium -One
Highway Speeds MediumWarmTwo
City Traffic Maximum GCWR -Three
Highway Speeds Maximum GCWR -Four
Uphill Grade Maximum GCWR HotFive
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228STARTING AND OPERATING
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 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 (64 km/h) and 87 mph
(140 km/h). The 4500/5500 Series maximum
vehicle speed can be set between 40 mph
(64 km/h) and 85 mph (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.
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)

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256STARTING AND OPERATING
AIR SUSPENSION SYSTEM — IF EQUIPPED
DESCRIPTION
This air suspension system is a rear leveling ride
height system. The main purpose of this system
is to maintain the truck’s rear ride height level.
There are two selectable heights that can be
chosen based on your operating conditions.
The system requires that the ignition be in the
ON/RUN position or the engine running with
zero vehicle speed for all user requested
changes and load leveling.

Rear Leveling Ride Height Switch
Normal Ride Height (NRH)
– This is the standard
position of the suspension and is meant for
normal driving. It will automatically adjust to
maintain the rear ride height as conditions
change.
Alternate Trailer Height (ATH) – Lowers the
vehicle approximately 1 inch (25 mm) for a level
truck, to be used as required while trailer
towing. It will automatically adjust to maintain
the rear ride height as conditions change.
Trailer Decoupling/Unloading - The air
suspension system will continue to load level
after the vehicle has been turned off for
10 minutes without compressor activation. This
allows for easy removal of a trailer and/or load
from the back of the truck by maintaining the
ride height. After 10 minutes you will need to
turn the ignition to the run position for the air
suspension to re-level due to addition/removal
of load in the vehicle. If the air suspension
system is disabled using the settings menu (Tire
Jack Mode, Transport Mode, Alignment Mode,
or Bed Lowering Mode) the system will remain
disabled when the vehicle is turned off.
Reactivating the air suspension can be
accomplished via the settings menu or driving the vehicle above 5 mph (8 km/h) for Tire Jack
Mode, Alignment Mode, Transport Mode and
Bed Lowering Mode.
NOTE:
Most 3500 models will not lower to Alternate
Trailer Height (ATH) when unloaded.
Refer to “Trailer Towing” in “Starting And
Operating” for further information.
AIR SUSPENSION MODES
The air suspension system has multiple modes
to protect the system in unique situations:
Tire/Jack Mode
To assist with changing a tire, the air
suspension system has a feature which allows
the automatic leveling to be disabled. This
mode is intended to be enabled with the engine
running. Refer to “Instrument Cluster Display”
WARNING!
The air suspension system uses a high
pressure volume of air to operate the system.
To avoid personal injury or damage to the
system, see an authorized dealer for service.

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STARTING AND OPERATING257
in “Getting To Know Your Instrument Panel” or
“Uconnect Settings” in “Multimedia” (if
equipped with a touch screen radio) for further
information.
NOTE:
This mode is intended to be enabled with the
engine running.
Transport Mode
For towing your vehicle with four wheels off the
road, the air suspension system has a feature
which will put the vehicle below Normal Ride
Height (NRH) and disable the automatic load
leveling system. This mode is intended to be
enabled with engine running. Refer to
“Instrument Cluster Display” in “Getting To
Know Your Instrument Panel” or “Uconnect
Settings” in “Understanding Your Instrument
Panel” if equipped with a touch screen radio for
further information.
NOTE:
This mode is intended to be enabled with the
engine running. Wheel Alignment Mode
Before performing a wheel alignment this mode
must be enabled. Refer to “Instrument Cluster
Display” in “Getting To Know Your Instrument
Panel” or “Uconnect Settings” in “Multimedia”
(if equipped with a touch screen radio) for
further information.
NOTE:
This mode is intended to be enabled with the
engine running.
Bed Lowering Mode
This setting is used to lower the rear suspension
to the lowest possible height and disable the air
suspension system. It enables easier loading/
unloading of the truck and makes it easier to
hook up trailers. Refer to “Instrument Cluster
Display” in “Getting To Know Your Instrument
Panel” or “Uconnect Settings” in
“Understanding Your Instrument Panel” if
equipped with a touch screen radio for further
information.
Protection Strategy
In order to “protect” the air suspension system,
the vehicle will disable load leveling as required
(suspension overloaded, battery charge low,
etc.). Load leveling will automatically resume as
soon as system operation requirements are
met. See an authorized dealer if system does
not resume.
INSTRUMENT CLUSTER DISPLAY
M
ESSAGES
When the appropriate conditions exist, a
message will appear in the instrument cluster
display. Refer to “Instrument Cluster Display” in
“Getting To Know Your Instrument Panel” for
further information.
An audible chime will be heard whenever a
system error has been detected.
See an authorized dealer for system service if
normal operation does not resume.5

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STARTING AND OPERATING261
SAFE OFF-ROAD DRIVING — POWER
WAGON ONLY
OFF-ROAD DRIVING TIPS AND VEHICLE
C
HARACTERISTICS
Your vehicle has excellent on and off-road
capabilities. These off-road capabilities will
allow you to explore those wilderness trails
where few travel, providing a source of exciting
and satisfying recreation. Before you venture
out, you should contact your local governmental
agency to determine the designated Off-Road
Vehicle (ORV) trails or recreation areas. You
should always tread lightly and only use
established roads, trails or ORV recreational
areas. The National Forest Service, Bureau of Land
Management, or local Department of Natural
Resources are a wealth of information and
usually have maps with marked trails.
Skid Plates And Underbody Protection
Steel skid plates protect the major driveline
components of the truck including the fuel tank,
transfer case and steering damper. In addition,
this vehicle is equipped with boxed cross
members and fore/aft rails. This additional
protection allows the vehicle to be utilized in
severe off-road situations that would be
considered impassable by a normal truck.
Ramp Travel Index (RTI)

The RTI is the distance, in inches, that you can
drive your vehicle with one wheel on a 20-degree
ramp without lifting any other wheel off the
ground. This distance up the ramp divided by the
wheelbase of the vehicle and multiplied by 1,000
is the RTI. This vehicle has an RTI of 429
(connected sway bar) or an RTI of 538
(disconnected sway bar), which means you can
articulate one front wheel 22 inches (56 cm) or
27.5 inches (70cm) in the air while the other
three wheels remain in contact with the ground.

Water Fording Characteristics

Water fording characteristic is the vehicle's ability
to cross a body of still water, where the
powertrain and drivetrain are safe from water
ingestion. This vehicle has high water fording
characteristics with the ability to cross a pool of
water, without stopping, 24 inches (60 cm) deep
at a maximum speed of 10 mph (16 km/h) and a
pool of water 30 inches (76 cm) deep at a
maximum speed of 5 mph (8 km/h), both with an
entrance ramp angle of 1.3 degrees.

Simultaneous Brake And Throttle
Operation
Many off-road driving conditions require the
simultaneous use of the brake and throttle (two
footed driving). When climbing rocks, logs, or
other stepped objects, using light brake
pressure with light throttle will keep the vehicle
from jerking or lurching. This technique is also
used when you need to stop and restart a
vehicle on a steep incline.
WARNING!
If the stabilizer/sway bar will not return to
On-Road mode, vehicle stability is reduced.
Do not attempt to drive the vehicle over
18 mph (29 km/h). Driving faster than
18 mph (29 km/h) may cause loss of control
of the vehicle, which could result in serious
injury or death. Contact your local service
center for assistance.
CAUTION!
The door sill height is 25 inches (63.5 cm).
Water may intrude into the interior of the
vehicle at greater depths.
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266STARTING AND OPERATING
If You Stall Or Begin To Lose Headway – If you
stall or begin to lose headway while climbing
a steep hill, allow your vehicle to come to a
stop and immediately apply the brake.
Restart the engine and shift into REVERSE.
Back slowly down the hill allowing the
compression braking of the engine and trans -
mission to help regulate your speed. If the
brakes are required to control vehicle speed,
apply them lightly and avoid locking or skid-
ding the tires.DRIVING THROUGH WATER
Extreme care should be taken crossing any type
of water. Water crossings should be avoided if
possible and only be attempted when
necessary, in a safe responsible manner. You
should only drive through areas which are
designated and approved. You should tread
lightly and avoid damage to the environment.
You should know your vehicle's abilities and be
able to recover it if something goes wrong. You
should never stop or shut a vehicle off when
crossing deep water unless you ingested water
into the engine air intake. If the engine stalls do
not attempt to restart it. Determine if it has
ingested water first. The key to any crossing is
low and slow. You want to use FIRST gear in
4WD LOW and proceed very slowly with a
constant slow speed (3-5 mph [5–8 km/h]
maximum) and light throttle. Keep the vehicle
moving; do not try to accelerate through the
crossing. After crossing any water higher than
the bottom of the axle differentials, you should
inspect all of the vehicle fluids for signs of water
ingestion.
Before You Cross Any Type Of Water – As you
approach any type of water you need to
determine if you can cross it safely and
responsibly. If necessary, get out and walk
through the water or probe it with a stick. You
need to be sure of its depth, approach angle,
current and bottom condition. Be careful of
murky or muddy waters, check for hidden
obstacles. Make sure you will not be
intruding on any wildlife and you can recover
the vehicle if necessary. The key to a safe
crossing is the water depth, current and
bottom conditions. On soft bottoms the
vehicle will sink in, effectively increasing the
water level on the vehicle. Be sure to
consider this when determining the depth
and the ability to safely cross.
WARNING!
If the engine stalls or you lose headway or
cannot make it to the top of a steep hill or
grade, never attempt to turn around. To do so
may result in tipping and rolling the vehicle,
which may result in severe injury. Always back
carefully straight down a hill in REVERSE.
Never back down a hill in NEUTRAL using only
the vehicle brakes. Never drive diagonally
across a hill, always drive straight up or down.
CAUTION!
Water ingestion into the axles, transmission,
transfer case, engine or vehicle interior can
occur if you drive too fast or through too deep
of water. Water can cause permanent
damage to engine, driveline or other vehicle
components and your brakes will be less
effective once wet and/or muddy.

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STARTING AND OPERATING267
Crossing Puddles, Pools, Flooded Areas Or
Other Standing Water – Puddles, pools,
flooded or other standing water areas
normally contain murky or muddy waters.
These water types normally contain hidden
obstacles and make it difficult to determine
an accurate water depth, approach angle,
and bottom condition. Murky or muddy water
holes are where you want to hook up tow
straps prior to entering. This makes for a
faster, cleaner and easier vehicle recovery. If
you are able to determine you can safely
cross, than proceed using the low and slow
method.
Crossing Ditches, Streams, Shallow Rivers Or
Other Flowing Water – Flowing water can be
extremely dangerous. Never attempt to cross
a fast running stream or river even in shallow
water. Fast moving water can easily push
your vehicle downstream sweeping it out of
control. Even in very shallow water, a high
current can still wash the dirt out from around your tires putting you and your vehicle
in jeopardy. There is still a high risk of
personal injury and vehicle damage with
slower water currents in depths greater than
the vehicle's running ground clearance. You
should never attempt to cross flowing water
which is deeper than the vehicle's running
ground clearance. Even the slowest current
can push the heaviest vehicle downstream
out of control if the water is deep enough to
push on the large surface area of the
vehicle's body. Before you proceed deter
-
mine the speed of the current, the water's
depth, approach angle, bottom condition and
if there are any obstacles, then cross at an
angle heading slightly upstream using the
low and slow technique.
AIRING DOWN FOR OFF-ROAD DRIVING

Running lower tire pressure off-road can improve
your ride comfort and vehicle traction. Reducing
the tire air pressure allows the tire to bulge
slightly, improving its surface area for better
flotation and ability to mold or form to the ground
contour. Different terrain, tires, and vehicles
require different tire pressure. Hard surfaces like
rock and heavier vehicles require higher
pressures than softer surfaces such as sand and
lighter vehicles. You will need to experiment to
determine what is right for your situation. It is
easier and faster to let air out than it is to replace
it. Start high and lower it as required. Remember
you must return the tires to normal air pressure
before driving on road or at highway conditions.
Be sure you have a way to return the tires to their
normal on road air pressure.

CAUTION!
Muddy waters can reduce the cooling system
effectiveness by depositing debris onto the
radiator.
WARNING!
Never drive through fast moving deep water. It
can push your vehicle downstream, sweeping
it out of control. This could put you and your
passengers at risk of injury or drowning.CAUTION!
Reduced tire pressure increases the risk of
tire damage and may cause tire unseating
with total loss of air pressure. To reduce the
risk of tire unseating, while at a reduced tire
pressure, drive at slower speeds and avoid
sharp turns or abrupt maneuvers.
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274STARTING AND OPERATING

1. Inspect the winch, winch mount, and
synthetic rope for damage. Do not use the
winch if the mount is loose or rope shows
excessive wear, frays, or damage.

Winch Rope

2. Put on gloves.
3. Disengage the clutch to allow free spooling of the winch drum, rotate the clutch lever on
the winch to disengage. Freespooling
conserves battery power.
Free Spool Lever

4. Free the winch hook and attach the hook strap. Free the winch hook from its anchor
point. Attach the hook strap to the hook (if
not attached).

Hook Strap

Always inspect winch installation and
synthetic rope condition before operating
the winch. Frayed, kinked or damaged rope
must be replaced immediately. Loose or
damaged winch installation must be
corrected immediately.
Always be sure any element which can
interfere with safe winching operations is
removed prior to initiating winching.
Always keep remote control lead clear of
the drum, synthetic rope and rigging.
Inspect for cracks, pinches, frayed rope, or
loose connections. Replace if damaged.
Be careful not to pull the winch rope collar
through the rollers. Watch and listen to
winch for proper snugness.
Never power hook through fairlead. Could
cause damage.
CAUTION! (Continued)

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