2021 RAM PROMASTER tire pressure

STARTING AND OPERATING77
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 Gross
Axle Weight Rating (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.
OVERLOADING
The load carrying components (axle, springs,
tires, wheels, etc.) of your vehicle will provide
satisfactory service as long as you do not
exceed the Gross Vehicle Weight Rating (GVWR)
and the front and rear Gross Axle Weight Rating
(GAWR).
The best way to figure out the total weight of
your vehicle is to weigh it when it is fully loaded
and ready for operation. Weigh it on a
commercial scale to ensure that it is not over
the GVWR.
Figure out the weight on the front and rear axle
of the vehicle separately. It is important that you
distribute the load evenly over the front and rear
axles.
Overloading can cause potential safety hazards
and shorten useful service life. Heavier axles or
suspension components do not necessarily
increase the vehicle's GVWR.
LOADING
To load your vehicle properly, first figure out its
empty weight, axle-by-axle and side-by-side.
Store heavier items down low and be sure you
distribute their weight as evenly as possible.
Stow all loose items securely before driving. If
weighing the loaded vehicle shows that you
have exceeded either Gross Axle Weight Rating
(GAWR), but the total load is within the specified
Gross Vehicle Weight Rating (GVWR), you must
redistribute the weight. Improper weight
distribution can have an adverse effect on the
way your vehicle steers and handles and the
way the brakes operate.
NOTE:
Refer to the “Vehicle Certification Label” affixed
to the rear of the driver's door for your vehicle's
GVWR and GAWRs.
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82STARTING AND OPERATING
(Continued)
Towing Requirements — Tires
Do not attempt to tow a trailer while using a
compact spare tire.
Do not drive more than 50 mph (80 km/h) when towing while using a full size spare tire.
Proper tire inflation pressures are essential
to the safe and satisfactory operation of your
vehicle.
Check the trailer tires for proper tire inflation
pressures before trailer usage.
Check for signs of tire wear or visible tire
damage before towing a trailer.
Replacing tires with a higher load carrying
capacity will not increase the vehicle's GVWR
and GAWR limits.
For further information Ú page 240.
Towing Requirements — Trailer Brakes
Do not interconnect the hydraulic brake
system or vacuum system of your vehicle
with that of the trailer. This could cause inad -
equate braking and possible personal injury.
WARNING!
Make certain that the load is secured in the
trailer and will not shift during travel. When
trailering cargo that is not fully secured,
dynamic load shifts can occur that may be
difficult for the driver to control. You could
lose control of your vehicle and have a
collision.
When hauling cargo or towing a trailer, do
not overload your vehicle or trailer. Over -
loading can cause a loss of control, poor
performance or damage to brakes, axle,
engine, transmission, steering, suspension,
chassis structure or tires.
Safety chains must always be used
between your vehicle and trailer. Always
connect the chains to the hook retainers of
the vehicle hitch. Cross the chains under
the trailer tongue and allow enough slack
for turning corners.
Vehicles with trailers should not be parked
on a grade. When parking, apply the
parking brake on the tow vehicle. Put the
tow vehicle transmission in PARK. For
four-wheel drive vehicles, make sure the
transfer case is not in NEUTRAL. Always,
block or "chock" the trailer wheels.
GCWR must not be exceeded.
Total weight must be distributed between
the tow vehicle and the trailer such that the
following four ratings are not exceeded :
GVWR
GTW
GAWR
Tongue weight rating for the trailer
hitch utilized.
WARNING! (Continued)

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149
(Continued)
SAFETY
SAFETY FEATURES
ANTI-LOCK BRAKE SYSTEM (ABS)
The ABS is designed to aid the driver in
maintaining vehicle control under adverse
braking conditions. The system operates with a
separate computer to modulate hydraulic
pressure, to prevent wheel lock-up and to help
avoid skidding on slippery surfaces.
The system's pump motor runs during an ABS
stop to provide regulated hydraulic pressure.
The pump motor makes a low humming noise
during operation, which is normal.
The ABS includes an amber ABS Warning Light.
When the light is illuminated, the ABS is not
functioning. The system reverts to standard
non-anti-lock brakes. Placing the ignition in the
OFF mode and to the ON mode again may reset
the ABS if the fault detected was only
momentary.When you are in a severe braking condition
involving the use of the ABS, you will experience
some pedal drop as the vehicle comes to a stop.
This is the result of the system reverting to the
base brake system.
Engagement of the ABS may be accompanied
by a pulsing sensation. You may also hear a
clicking noise. These occurrences are normal
and indicate that the system is functioning
properly.
WARNING!
The ABS contains sophisticated electronic
equipment that may be susceptible to inter
-
ference caused by improperly installed or
high output radio transmitting equipment.
This interference can cause possible loss of
anti-lock braking capability. Installation of
such equipment should be performed by
qualified professionals.
Pumping of the Anti-Lock Brakes will
diminish their effectiveness and may lead
to a collision. Pumping makes the stopping
distance longer. Just press firmly on your
brake pedal when you need to slow down or
stop.
The ABS cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase braking or steering efficiency
beyond that afforded by the condition of the
vehicle brakes and tires or the traction
afforded.
The ABS cannot prevent collisions,
including those resulting from excessive
speed in turns, following another vehicle
too closely, or hydroplaning.
The capabilities of an ABS equipped vehicle
must never be exploited in a reckless or
dangerous manner that could jeopardize
the user’s safety or the safety of others.
WARNING! (Continued)
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154SAFETY
Towing With HSA
HSA will also provide assistance to mitigate roll
back while towing a trailer.
Traction Control System (TCS)
TCS monitors the amount of wheel spin of each
of the driven wheels. If wheel spin is detected,
brake pressure is applied to the slipping
wheel(s) and engine power is reduced, to
provide enhanced acceleration and stability. A
feature of the TCS, Brake Limited Differential
(BLD), functions similarly to a limited slip
differential and controls the wheel spin across a
driven axle. If one wheel on a driven axle is
spinning faster than the other, the system will
apply the brake of the spinning wheel. This will
allow more engine torque to be applied to the
wheel that is not spinning. This feature remains
active even if the ESC is in the “Partial Off”
mode.
The ESC Activation/Malfunction Indicator Light
(in the instrument cluster) will start to flash as
soon as the tires lose traction and the wheels
begin to spin. This indicates that the TCS is
active. If the indicator light flashes during
acceleration, ease up on the accelerator and
apply as little throttle as possible. Be sure to
adapt your speed and driving to the prevailing
road conditions, and do not switch off the ESC
or TCS.
Trailer Sway Control (TSC) — If Equipped
TSC uses sensors in the vehicle to recognize an
excessively swaying trailer and will take the
appropriate actions to attempt to stop the sway.
The system may reduce engine power and apply
the brake of the appropriate wheel(s) to
counteract the sway of the trailer.
WARNING!
If you use a trailer brake controller with your
trailer, the trailer brakes may be activated
and deactivated with the brake switch. If
so, there may not be enough brake pres -
sure to hold both the vehicle and the trailer
on a hill when the brake pedal is released.
In order to avoid rolling down an incline
while resuming acceleration, manually acti -
vate the trailer brake or apply more vehicle
brake pressure prior to releasing the brake
pedal.
HSA is not a parking brake. Always apply
the parking brake fully when exiting your
vehicle. Also, be certain to place the trans -
mission in PARK.
Failure to follow these warnings can result
in a collision or serious personal injury.
WARNING!
The TCS cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase the traction afforded.
The TCS cannot prevent collisions,
including those resulting from excessive
speed in turns, or hydroplaning.
The capabilities of a TCS-equipped vehicle
must never be exploited in a reckless or
dangerous manner, which could jeopardize
the user's safety or the safety of others.

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SAFETY161
More cautious drivers that do not mind
frequent warnings may prefer this
setting.
Medium
When the sensitivity of FCW is set to the
“Medium” setting and the system status
is “Only Warning”, this allows the system
to warn the driver of a possible collision
with the vehicle in front using audible/
visual warnings.
Near
When the sensitivity of FCW is set to the
“Near” setting and the system status is
“Only Warning”, this allows the system to
warn the driver of a possible closer colli -
sion with the vehicle in front using
audible/visual warnings.
This setting provides less reaction time
than the “Far” and “Medium” settings,
which allows for a more dynamic driving
experience.
More dynamic or aggressive drivers that
want to avoid frequent warnings may
prefer this setting.
FCW Limited Warning
If the instrument cluster displays “FCW Limited
Functionality” or “FCW Limited Functionality
Clean Front Windshield” momentarily, there
may be a condition that limits FCW functionality.
Although the vehicle is still drivable under
normal conditions, the active braking may not
be fully available. Once the condition that
limited the system performance is no longer
present, the system will return to its full
performance state. If the problem persists, see
an authorized dealer.
Service FCW Warning
If the system turns off, and the instrument
cluster displays: “FCW Unavailable Service
Required”, this indicates there is an internal
system fault. Although the vehicle is still
drivable under normal conditions, have the
system checked by an authorized dealer.
TIRE PRESSURE MONITORING SYSTEM
(TPMS)
The Tire Pressure Monitoring System (TPMS)
will warn the driver of a low tire pressure based
on the vehicle recommended cold placard
pressure.
The tire pressure will vary with temperature by
about 1 psi (7 kPa) for every 12°F (6.5°C). This
means that when the outside temperature
decreases, the tire pressure will decrease. Tire
pressure should always be set based on cold
inflation tire pressure. This is defined as the tire
pressure after the vehicle has not been driven
for at least three hours, or driven less than
1 mile (1.6 km) after a three hour period. The
cold tire inflation pressure must not exceed the
maximum inflation pressure molded into the
tire sidewall. The tire pressure will also increase
as the vehicle is driven — this is normal and
there should be no adjustment for this
increased pressure.
See Úpage 240 on how to properly inflate the
vehicle’s tires.
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162SAFETY
The TPMS will warn the driver of a low tire
pressure if the tire pressure falls below the
low-pressure warning limit for any reason,
including low temperature effects and natural
pressure loss through the tire.
The TPMS will continue to warn the driver of low
tire pressure as long as the condition exists,
and will not turn off until the tire pressure is at
or above the recommended cold placard
pressure. Once the low tire pressure warning
(TPMS Warning Light) illuminates, you must
increase the tire pressure to the recommended
cold placard pressure in order for the TPMS
Warning Light to turn off. The system will
automatically update and the TPMS Warning
Light will turn off once the system receives the
updated tire pressures. The vehicle may need to
be driven for up to 20 minutes above 15 mph
(24 km/h) in order for the TPMS to receive this
information. NOTE:
When filling warm tires, the tire pressure may
need to be increased up to an additional 4 psi
(28 kPa) above the recommended cold placard
pressure in order to turn the TPMS Warning
Light off.
For example, your vehicle may have a
recommended cold (parked for more than three
hours) placard pressure of 30 psi (207 kPa). If
the ambient temperature is 68°F (20°C) and
the measured tire pressure is 27 psi (186 kPa),
a temperature drop to 20°F (-7°C) will
decrease the tire pressure to approximately
23 psi (158 kPa). This tire pressure is
sufficiently low enough to turn on the TPMS
Warning Light. Driving the vehicle may cause
the tire pressure to rise to approximately 27 psi
(186 kPa), but the TPMS Warning Light will still
be on. In this situation, the TPMS Warning Light
will turn off only after the tires are inflated to the
vehicle’s recommended cold placard pressure
value.CAUTION!
The TPMS has been optimized for the orig
-
inal equipment tires and wheels. TPMS
pressures and warning have been estab -
lished for the tire size equipped on your
vehicle. Undesirable system operation or
sensor damage may result when using
replacement equipment that is not of the
same size, type, and/or style. Aftermarket
wheels can cause sensor damage.
Using aftermarket tire sealants may cause
the Tire Pressure Monitoring System
(TPMS) sensor to become inoperable. After
using an aftermarket tire sealant it is
recommended that you take your vehicle to
an authorized dealership to have your
sensor function checked.
After inspecting or adjusting the tire pres -
sure always reinstall the valve stem cap.
This will prevent moisture and dirt from
entering the valve stem, which could
damage the TPMS sensor.

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SAFETY163
NOTE:
The TPMS is not intended to replace normal
tire care and maintenance or to provide
warning of a tire failure or condition.
The TPMS should not be used as a tire pres -
sure gauge while adjusting your tire pressure.
Driving on a significantly underinflated tire
causes the tire to overheat and can lead to
tire failure. Underinflation also reduces fuel
efficiency and tire tread life, and may affect
the vehicle’s handling and stopping ability.
The TPMS is not a substitute for proper tire
maintenance, and it is the driver’s responsi -
bility to maintain correct tire pressure using
an accurate tire pressure gauge, even if
underinflation has not reached the level to
trigger illumination of the TPMS Warning
Light.
Seasonal temperature changes will affect
tire pressure, and the TPMS will monitor the
actual tire pressure in the tire Ú page 274.
Base System
This is the TPMS warning indicator
located in the instrument cluster.
The TPMS uses wireless technology with wheel
rim mounted electronic sensors to monitor 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
regularly and to maintain the proper pressure.
The TPMS consists of the following
components:
Receiver Module
Four Tire Pressure Monitoring System
sensors
Tire Pressure Monitoring System Warning
Light
Tire Pressure Monitoring Low Pressure
Warnings
The Tire Pressure Monitoring System Warning
Light will illuminate in the instrument cluster, an
audible chime will be activated, and the “Check
tire pressure” message will display when one or
more of the four active road tire pressures are
low. Should this occur, you should stop as soon
as possible, check the inflation pressure of
each tire on your vehicle, and inflate each tire to
the vehicle’s recommended cold placard
pressure value. The system will automatically
update and the Tire Pressure Monitoring
System warning Light will extinguish once the
updated tire pressures have been received.
The vehicle may need to be driven for up to
20 minutes above 15 mph (24 km/h) to receive
this information.
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164SAFETY
Check TPMS Warnings
The Tire Pressure Monitoring System Warning
Light will flash on and off for 75 seconds and
remain on solid when a system fault is detected,
an audible chime will be activated and the “Tire
Pressure Monitoring Unavailable” message will
display. If the ignition key is cycled, this
sequence will repeat providing the system fault
still exists. The TPMS Warning Light will turn off
when the fault condition no longer exists. A
system fault can occur with any of the following
scenarios:
Jamming due to electronic devices or driving
next to facilities emitting the same radio
frequencies as the TPMS sensors
Installing some form of aftermarket window
tinting that affects radio wave signals
Snow or ice around the wheels or wheel
housings
Using tire chains on the vehicle
Using wheels/tires not equipped with TPMS
sensors NOTE:
Your vehicle is equipped with a regular size
spare wheel.

1. The spare tire does not have a TPMS
sensor. Therefore, the TPMS will not
monitor the pressure in the spare tire.

2. If a spare tire not equipped with the Tire Pressure Monitoring system sensor is used,
the TPMS Warning Light will turn on,
flashing for 75 seconds and then remaining
solid for each subsequent ignition key cycle.
3. Once you repair or replace the original road tire and reinstall it on the vehicle in place of
the spare tire, the TPMS will update
automatically and the Tire Pressure
Monitoring System Warning Light will
extinguish once the updated tire pressures
have been received. The vehicle may need
to be driven for up to 20 minutes above
15 mph (24 km/h) to receive this
information.
NOTE:
For correct Tire Pressure Monitoring System
behavior, please wait for about 20 minutes in
key-off during each tire substitution.
OCCUPANT RESTRAINT SYSTEMS
Some of the most important safety features in
your vehicle are the restraint systems:
OCCUPANT RESTRAINT SYSTEMS
F
EATURES
Seat Belt Systems
Supplemental Restraint Systems (SRS) Air
Bags
Child Restraints

Some of the safety features described in this
section may be standard equipment on some
models, or may be optional equipment on others.
If you are not sure, ask an authorized dealer.

IMPORTANT SAFETY PRECAUTIONS
Please pay close attention to the information in
this section. It tells you how to use your restraint
system properly, to keep you and your
passengers as safe as possible.

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