2020 Ram 3500 inflation pressure

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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STARTING AND OPERATING331
(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. Refer to “Tires” in “Servicing And
Maintenance” for proper tire inflation proce -
dures.
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. Refer to
“Tires” in “Servicing And Maintenance” for
the proper inspection procedure.
When replacing tires, refer to “Tires” in
“Servicing And Maintenance” for the proper
tire replacement procedures. Replacing tires
with a higher load carrying capacity will not
increase the vehicle's GVWR and GAWR
limits.
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.
An electronically actuated trailer brake
controller is required when towing a trailer
with electronically actuated brakes. When
towing a trailer equipped with a hydraulic
surge actuated brake system, an electronic
brake controller is not required.
Trailer brakes are recommended for trailers
over 1,000 lbs (453 kg) and required for
trailers in excess of 2,000 lbs (907 kg).
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.
WARNING! (Continued)
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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372IN CASE OF EMERGENCY
6. Finish tightening the lug nuts. Push down on
the lug wrench while at the end of the
handle for increased leverage. Tighten the
lug nuts in a star pattern until each nut has
been tightened twice. For the correct lug nut
torque refer to “Wheel And Tire Torque
Specifications” in “Technical Specifi -
cations”. If in doubt about the correct
tightness, have them checked with a torque
wrench by an authorized dealer or service
station.
7. Install the wheel center cap and remove the wheel blocks. Do not install chrome or
aluminum wheel center caps on the spare
wheel. This may result in cap damage. 8. Lower the jack to its fully closed position.
Stow the replaced tire, jack, and tools as
previously described.
NOTE:
The bottle jack will not lower by turning the dial
(thumbwheel) by hand, it may be necessary to
use the jack driver in order to lower the jack.
9. Adjust the tire pressure when possible.
NOTE:
Do not oil wheel studs. For chrome wheels, do
not substitute with chrome plated lug nuts.
TO STOW THE FLAT OR SPARE
NOTE:
Have the flat tire repaired or replaced immedi -
ately.

1. Turn the wheel so that the valve stem is facing the ground and toward the rear of
the vehicle for convenience in checking the
spare tire inflation. Slide the wheel retainer
through the center of the wheel.

Reinstalling The Retainer

2. Lift the spare tire with one hand to give clearance to tilt the retainer at the end of
the cable and position it properly across the
wheel opening.
WARNING!
A loose tire or jack thrown forward in a
collision or hard stop, could endanger the
occupants of the vehicle. Always stow the jack
parts and the spare tire in the places
provided.
WARNING!
A loose tire or jack thrown forward in a
collision or hard stop could endanger the
occupants of the vehicle. Always stow the jack
parts and the spare tire in the places
provided. Have the deflated (flat) tire repaired
or replaced immediately.

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SERVICING AND MAINTENANCE431
H = Speed Symbol
A symbol indicating the range of speeds at which a tire can carry a load corresponding to its load index under certain operating conditions
The maximum speed corresponding to the speed symbol should only be achieved under specified operating conditions (i.e., tire pressure, vehicle
loading, road conditions, and posted speed limits)
Load Identification:
Absence of the following load identification symbols on the sidewall of the tire indicates a Standard Load (SL) tire:
XL = Extra load (or reinforced) tire, or
LL = Light load tire or
C, D, E, F, G = Load range associated with the maximum load a tire can carry at a specified pressure
Maximum Load – Maximum load indicates the maximum load this tire is designed to carry
Maximum Pressure – Maximum pressure indicates the maximum permissible cold tire inflation pressure for this tire
EXAMPLE:
7

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SERVICING AND MAINTENANCE433
Tire Terminology And Definitions
Tire Loading And Tire Pressure
NOTE:
The proper cold tire inflation pressure is listed
on the driver’s side B-Pillar or the rear edge of
the driver's side door.
Check the inflation pressure of each tire,
including the spare tire (if equipped), at least
monthly and inflate to the recommended
pressure for your vehicle.

Example Tire Placard Location (Door)Example Tire Placard Location (B-Pillar)

Term Definition
B-PillarThe vehicle B-Pillar is the structural member of the body located behind the front door.
Cold Tire Inflation Pressure Cold tire inflation pressure 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 sitting for a
minimum of three hours. Inflation pressure is measured in units of PSI (pounds per
square inch) or kPa (kilopascals).
Maximum Inflation Pressure The maximum inflation pressure is the maximum permissible cold tire inflation pressure
for this tire. The maximum inflation pressure is molded into the sidewall.
Recommended Cold Tire Inflation Pressure Vehicle manufacturer's recommended cold tire inflation pressure as shown on the tire
placard.
Tire Placard A label permanently attached to the vehicle describing the vehicle’s loading capacity,
the original equipment tire sizes and the recommended cold tire inflation pressures.
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434SERVICING AND MAINTENANCE
Tire And Loading Information Placard

Tire And Loading Information Placard

This placard tells you important information
about the:

1. Number of people that can be carried in the vehicle.

2. Total weight your vehicle can carry.
3. Tire size designed for your vehicle.
4. Cold tire inflation pressures for the front, rear, and spare tires.Loading
The vehicle maximum load on the tire must not
exceed the load carrying capacity of the tire on
your vehicle. You will not exceed the tire's load
carrying capacity if you adhere to the loading
conditions, tire size, and cold tire inflation
pressures specified on the Tire and Loading
Information placard in “Vehicle Loading” in the
“Starting And Operating” section of this manual.
NOTE:
Under a maximum loaded vehicle condition,
gross axle weight ratings (GAWRs) for the front
and rear axles must not be exceeded.
For further information on GAWRs, vehicle
loading, and trailer towing, refer to “Vehicle
Loading” in the “Starting And Operating”
section of this manual.
To determine the maximum loading conditions
of your vehicle, locate the statement “The
combined weight of occupants and cargo
should never exceed XXX kg or XXX lbs” on the
Tire and Loading Information placard. The
combined weight of occupants, cargo/luggage
and trailer tongue weight (if applicable) should
never exceed the weight referenced here.
Steps For Determining Correct Load
Limit—
(1) Locate the statement “The combined
weight of occupants and cargo should
never exceed XXX kg or XXX lbs.” on your
vehicle's placard.
(2) Determine the combined weight of
the driver and passengers that will be
riding in your vehicle.
(3) Subtract the combined weight of the
driver and passengers from XXX kg or
XXX lbs.
(4) The resulting figure equals the
available amount of cargo and luggage
load capacity. For example, if “XXX”
amount equals 1400 lbs. and there will
be five 150 lb passengers in your
vehicle, the amount of available cargo
and luggage load capacity is 650 lbs.
(1400-750 (5x150) = 650 lbs.)

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SERVICING AND MAINTENANCE435
(Continued)
(5) Determine the combined weight of
luggage and cargo being loaded on the
vehicle. That weight may not safely
exceed the available cargo and luggage
load capacity calculated in Step 4.
(6) If your vehicle will be towing a trailer,
load from your trailer will be transferred
to your vehicle. Consult this manual to
determine how this reduces the
available cargo and luggage load
capacity of your vehicle.
Metric Example For Load Limit
For example, if “XXX” amount equals 635 kg
and there will be five 68 kg passengers in your
vehicle, the amount of available cargo and
luggage load capacity is 295 kg (635-340
(5x68) = 295 kg) as shown in step 4. NOTE:
If your vehicle will be towing a trailer, load
from your trailer will be transferred to your
vehicle. The following table shows examples
on how to calculate total load, cargo/
luggage, and towing capacities of your
vehicle with varying seating configurations
and number and size of occupants. This table
is for illustration purposes only and may not
be accurate for the seating and load carry
capacity of your vehicle.
For the following example, the combined
weight of occupants and cargo should never
exceed 865 lbs (392 kg).
TIRES — GENERAL INFORMATION
Tire Pressure
Proper tire inflation pressure is essential to the
safe and satisfactory operation of your vehicle.
Four primary areas are affected by improper tire
pressure:
Safety
Fuel Economy
Tread Wear
Ride Comfort and Vehicle Stability
Safety
WARNING!
Overloading of your tires is dangerous.
Overloading can cause tire failure, affect
vehicle handling, and increase your stopping
distance. Use tires of the recommended load
capacity for your vehicle. Never overload
them.
WARNING!
Improperly inflated tires are dangerous and
can cause collisions.
Underinflation increases tire flexing and
can result in overheating and tire failure.
Overinflation reduces a tire's ability to
cushion shock. Objects on the road and
chuckholes can cause damage that result
in tire failure.
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436SERVICING AND MAINTENANCE
Both underinflation and overinflation affect the
stability of the vehicle and can produce a feeling
of sluggish response or over responsiveness in
the steering.
NOTE:
Unequal tire pressures from side to side may
cause erratic and unpredictable steering
response.
Unequal tire pressure from side to side may
cause the vehicle to drift left or right. Fuel Economy
Underinflated tires will increase tire rolling
resistance resulting in higher fuel consumption.
Tread Wear
Improper cold tire inflation pressures can cause
abnormal wear patterns and reduced tread life,
resulting in the need for earlier tire
replacement.
Ride Comfort And Vehicle Stability
Proper tire inflation contributes to a
comfortable ride. Overinflation produces a
jarring and uncomfortable ride.
Tire Inflation Pressures
The proper cold tire inflation pressure is listed
on the driver's side B-Pillar or rear edge of the
driver's side door.
At least once a month:
Check and adjust tire pressure with a good
quality pocket-type pressure gauge. Do not
make a visual judgement when determining
proper inflation. Tires may look properly
inflated even when they are under-inflated.
Inspect tires for signs of tire wear or visible
damage.
Inflation pressures specified on the placard are
always “cold tire inflation pressure”. Cold tire
inflation pressure 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 sitting for a minimum of three hours. The
cold tire inflation pressure must not exceed the
maximum inflation pressure molded into the
tire sidewall.
Check tire pressures more often if subject to a
wide range of outdoor temperatures, as tire
pressures vary with temperature changes.

Tire pressures change by approximately 1 psi
(7 kPa) per 12°F (7°C) of air temperature
change. Keep this in mind when checking tire
pressure inside a garage, especially in the
Winter.

Example: If garage temperature = 68°F (20°C)
and the outside temperature = 32°F (0°C) then
Overinflated or underinflated tires can
affect vehicle handling and can fail
suddenly, resulting in loss of vehicle
control.
Unequal tire pressures can cause steering
problems. You could lose control of your
vehicle.
Unequal tire pressures from one side of the
vehicle to the other can cause the vehicle
to drift to the right or left.
Always drive with each tire inflated to the
recommended cold tire inflation pressure.
WARNING!
(Continued)CAUTION!
After inspecting or adjusting the tire pressure,
always reinstall the valve stem cap. This will
prevent moisture and dirt from entering the
valve stem, which could damage the valve
stem.

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