2020 Ram 3500 tire pressure

SAFETY171
Operation:
The horn will chirp once when the selected
pressure is reached to let the user know
when to stop inflating or deflating the tire.
The horn will chirp three times if the tire is
over inflated or over deflated and will
continue to chirp every five seconds if the
user continues to inflate or deflate the tire.
The horn will chirp once again when enough
air is added or removed to reach proper
selected pressure level.
Tire Pressure Information System (TPIS)
3500 Series Trucks
Your vehicle may be equipped with a Tire
Pressure Information System (TPIS).
The Tire Pressure Information System (TPIS)
uses wireless technology with wheel rim
mounted electronic sensors to transmit tire
pressure levels. Sensors mounted to each
wheel as part of the valve stem transmit tire
pressure readings to the receiver module. NOTE:
It is particularly important for you to check the
tire pressure in all of the tires on your vehicle
monthly and to maintain the proper pressure.
The TPIS consists of the following components:
Receiver module
Four TPM sensors (Single Rear Wheel (SRW)
applications)
Six TPM sensors (Dual Rear Wheel (DRW)
applications)
Pressure display in the instrument cluster
The TPIS system will display all four (Single Rear
Wheel (SRW) applications) or six (Dual Rear
Wheel (DRW) applications) tire pressure values
in the instrument cluster display.
If a system fault is detected, the instrument
cluster will display a "SERVICE TPM SYSTEM"
message for a minimum of five seconds and
then display dashes (- -) in place of the pressure
value to indicate which sensor is not being
received. If the ignition switch is cycled, this sequence will
repeat, providing the system fault still exists. If
the system fault no longer exists, the "SERVICE
TPM SYSTEM" message will no longer be
displayed, and a pressure value will display in
place of the dashes. A system fault can occur
due to any of the following:
Signal interference due to electronic devices
or driving next to facilities emitting the same
radio frequencies as the TPM sensors.
Installing aftermarket window tinting that
contains materials that may block radio wave
signals.
Accumulation of snow or ice around the
wheels or wheel housings.
Using tire chains on the vehicle.
Using wheels/tires not equipped with TPM
sensors.
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212SAFETY
PERIODIC SAFETY CHECKS YOU SHOULD
M
AKE OUTSIDE THE VEHICLE
Tires
Examine tires for excessive tread wear and
uneven wear patterns. Check for stones, nails,
glass, or other objects lodged in the tread or
sidewall. Inspect the tread for cuts and cracks.
Inspect sidewalls for cuts, cracks, and bulges.
Check the wheel bolts for tightness. Check the
tires (including spare) for proper cold inflation
pressure.
Lights
Have someone observe the operation of brake
lights and exterior lights while you work the
controls. Check turn signal and high beam
indicator lights on the instrument panel.
Door Latches
Check for proper closing, latching, and locking.
Fluid Leaks
Check area under the vehicle after overnight
parking for fuel, coolant, oil, or other fluid leaks.
Also, if gasoline fumes are detected or if fuel, or
brake fluid leaks are suspected, the cause
should be located and corrected immediately.
It is recommended to only use mild soap
and water to clean your floor mats. After
cleaning, always check your floor mat has
been properly installed and is secured to
your vehicle using the floor mat fasteners
by lightly pulling mat.
WARNING! (Continued)

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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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254STARTING AND OPERATING
met. Refer to “Shifting Procedure – Manually
Shifted Transfer Case” in this section for further
information.
The 4H and 4L positions are intended for loose,
slippery road surfaces only. Driving in the 4H
and 4L positions on dry, hard surfaced roads
may cause increased tire wear and damage to
the driveline components.
The “Transfer Case Position Indicator Light” in
the instrument cluster will alert the driver that
the vehicle is in four-wheel drive and that the
front and rear driveshafts are locked together.
This light will illuminate when the transfer case
is shifted into either the 4H or 4L position. There
is no light for the 2H or NEUTRAL positions on
some models.
When operating your vehicle in 4L, the engine
speed is approximately three times that of the
2H or 4H positions at a given road speed. Take
care not to overspeed the engine and do not
exceed 25 mph (40 km/h).
Proper operation of four-wheel drive vehicles
depends on tires of equal size, type and
circumference on each wheel. Any difference
will adversely affect shifting and can cause
damage to the drivetrain. NOTE:
Do not attempt to make a shift while only the
front or rear wheels are spinning, as this can
cause damage to driveline components.
Because four-wheel drive provides improved
traction, there is a tendency to exceed safe
turning and stopping speeds. Do not go faster
than road conditions permit.
NOTE:
Delayed shifts out of four-wheel drive may be
experienced due to uneven tire wear, low or
uneven tire pressures, excessive vehicle
loading, or cold temperatures.Two-Wheel Drive High Range (2H)
Two-Wheel Drive High Range — This range is for
normal street and highway driving on dry hard
surfaced roads.
Four-Wheel Drive High Range (4H)
Four-Wheel Drive High Range — This range locks
the front and rear driveshafts together forcing
the front and rear wheels to rotate at the same
speed. Additional traction for loose, slippery
road surfaces only.
N (Neutral)
N (Neutral) — This range disengages the front
and rear driveshafts from the powertrain. To be
used for flat towing behind another vehicle.
Refer to “Recreational Towing” in “Starting And
Operating” for further information.
Four-Wheel Drive Low Range (4L)
Four-Wheel Drive Low Range — This range locks
the front and rear driveshafts together forcing
the front and rear wheels to rotate at the same
speed. Additional traction and maximum pulling
power for loose, slippery road surfaces only. Do
not exceed 25 mph (40 km/h).
WARNING!
You or others could be injured or killed if you
leave the vehicle unattended with the transfer
case in the NEUTRAL position without first
fully engaging the parking brake. The transfer
case NEUTRAL position disengages both the
front and rear drive shafts from the
powertrain and will allow the vehicle to roll,
even if the transmission is in PARK. The
parking brake should always be applied when
the driver is not in the vehicle.

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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 OPERATING263
They are normally full of debris from previous
vehicles getting stuck. As a good practice
before entering any mud hole, get out and
determine how deep it is, if there are any
hidden obstacles and if the vehicle can be
safely recovered if stuck.
Sand – Soft sand is very difficult to travel
through with full tire pressure. When crossing
soft sandy spots in a trail, maintain your
vehicle's momentum and do not stop. The
key to driving in soft sand is using the appro -
priate tire pressure, accelerating slowly,
avoiding abrupt maneuvers and maintaining
the vehicle's momentum. If you are going to
be driving on large soft sandy areas or dunes,
reduce your tire pressure to a minimum of
15 psi (103 kPa) to allow for a greater tire
surface area. Reduced tire pressure will dras -
tically improve your traction and handling,
while driving on the soft sand, but you must
return the tires to normal air pressure before
driving on pavement or other hard surfaces.
Be sure you have a way to air the tires back
up prior to reducing the pressure.
CROSSING OBSTACLES (ROCKS AND
O
THER HIGH POINTS)
While driving off road, you will encounter many
types of terrain. These varying types of terrain
bring different types of obstacles. Before
proceeding review the path ahead to determine
the correct approach and your ability to safely
recover the vehicle if something goes wrong.
Keeping a firm grip on the steering wheel, bring
the vehicle to a complete stop and then inch the
vehicle forward until it makes contact with the
object. Apply the throttle lightly while holding a
light brake pressure and ease the vehicle up
and over the object.
Using A Spotter
There are many times where it is hard to see the
obstacle or determine the correct path.
Determining the correct path can be extremely
difficult when you are confronting many
obstacles. In these cases have someone guide
you over, through, or around the obstacle. Have
the person stand a safe distance in front of you
where they can see the obstacle, watch your
tires and undercarriage, and guide you through.
Crossing Large Rocks
When approaching large rocks, choose a path
which ensures you drive over the largest with
your tires. This will lift your undercarriage over
the obstacle. The tread of the tire is tougher and
thicker than the side wall and is designed to
take the abuse. Always look ahead and make
every effort to cross the large rocks with your
tires.
CAUTION!
Reduced tire pressures may cause tire
unseating and total loss of air pressure. To
reduce the risk of tire unseating, while at a
reduced tire pressure, reduce your speed and
avoid sharp turns or abrupt maneuvers.
WARNING!
Crossing obstacles can cause abrupt steering
system loading which could cause you to
loose control of your vehicle.
CAUTION!
Never attempt to straddle a rock that is
large enough to strike your axles or under -
carriage.
Never attempt to drive over a rock which is
large enough to contact the door sills.
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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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324STARTING AND OPERATING
system to operate properly at temperatures
below 12°F (-11°C). If your vehicle is not in
operation for an extended period of time with
temperatures below 12°F (-11°C), the DEF in
the tank may freeze. If the tank is overfilled and
freezes, it could be damaged. Therefore, do not
overfill the DEF tank.
Extra care should be taken when filling with
portable containers to avoid overfilling. Note the
level of the DEF gauge in your instrument
cluster. You may safely add a maximum of
2 Gallons (7.5 Liters) of DEF from portable
containers when your DEF gauge is reading
½ full.
VEHICLE LOADING
GROSS VEHICLE WEIGHT RATING
(GVWR)
The GVWR is the total permissible weight of your
vehicle including driver, passengers, vehicle,
options and cargo. The label also specifies
maximum capacities of front and rear axle
systems (GAWR). Total load must be limited so
GVWR and front and rear GAWR are not
exceeded.
PAYLOAD
The payload of a vehicle is defined as the
allowable load weight a truck can carry,
including the weight of the driver, all
passengers, options and cargo.
GROSS AXLE WEIGHT RATING (GAWR)
The GAWR is the maximum permissible load on
the front and rear axles. The load must be
distributed in the cargo area so that the GAWR
of each axle is not exceeded.
Each axle GAWR is determined by the
components in the system with the lowest load
carrying capacity (axle, springs, tires or wheels).
Heavier axles or suspension components
sometimes specified by purchasers for
increased durability does not necessarily
increase the vehicle's GVWR.
TIRE SIZE
The tire size on the Vehicle Certification Label
represents the actual tire size on your vehicle.
Replacement tires must be equal to the load
capacity of this tire size.
RIM SIZE
This is the rim size that is appropriate for the tire
size listed.
INFLATION PRESSURE
This is the cold tire inflation pressure for your
vehicle for all loading conditions up to full
GAWR.
CURB WEIGHT
The curb weight of a vehicle is defined as the
total weight of the vehicle with all fluids,
including vehicle fuel, at full capacity
conditions, and with no occupants or cargo
loaded into the vehicle. The front and rear curb
weight values are determined by weighing your
vehicle on a commercial scale before any
occupants or cargo are added.
LOADING
The actual total weight and the weight of the
front and rear of your vehicle at the ground can
best be determined by weighing it when it is
loaded and ready for operation.

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