2019 RAM CHASSIS CAB maintenance

452 SERVICING AND MAINTENANCE
Steps For Determining Correct Load Limit—
(1) Locate the statement “The combined weight of occu -
pants 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.)
(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 avail -
able 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 occu -
pants and cargo should never exceed 865 lbs (392 kg).

SERVICING AND MAINTENANCE 453
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. 7

454 SERVICING AND MAINTENANCE
(Continued)Tires — General Information
Tire Pressure
Proper tire inflation pressure is essential to the safe and satis -
factory operation of your vehicle. Four primary areas are
affected by improper tire pressure:
• Safety
• Fuel Economy
• Tread Wear
• Ride Comfort and Vehicle Stability
Safety
Both under-inflation and over-inflation 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.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. • 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 recom -
mended cold tire inflation pressure. WARNING! (Continued)

SERVICING AND MAINTENANCE 455
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.
Over-inflation 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 judge -
ment 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 infla -
tion 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 tempera -
ture 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 the cold tire inflation
pressure should be increased by 3 psi (21 kPa), which equals
1 psi (7 kPa) for every 12°F (7°C) for this outside temperature
condition. 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.
7

456 SERVICING AND MAINTENANCE
Tire pressure may increase from 2 to 6 psi (13 to 40 kPa)
during operation. DO NOT reduce this normal pressure
build up or your tire pressure will be too low.
Tire Pressures For High Speed Operation
The manufacturer advocates driving at safe speeds and
within posted speed limits. Where speed limits or conditions
are such that the vehicle can be driven at high speeds, main -
taining correct tire inflation pressure is very important.
Increased tire pressure and reduced vehicle loading may be
required for high-speed vehicle operation. Refer to an autho -
rized tire dealer or original equipment vehicle dealer for
recommended safe operating speeds, loading and cold tire
inflation pressures. Radial Ply Tires
Tire Repair
If your tire becomes damaged, it may be repaired if it meets
the following criteria:
• The tire has not been driven on when flat.
• The damage is only on the tread section of your tire (side -
wall damage is not repairable).
• The puncture is no greater than a ¼ of an inch (6 mm).
Consult an authorized tire dealer for tire repairs and addi -
tional information.
Damaged Run Flat tires, or Run Flat tires that have experi -
enced a loss of pressure should be replaced immediately
with another Run Flat tire of identical size and service
description (Load Index and Speed Symbol). Replace the tire
pressure sensor as well as it is not designed to be reused.WARNING!
High speed driving with your vehicle under maximum
load is dangerous. The added strain on your tires could
cause them to fail. You could have a serious collision. Do
not drive a vehicle loaded to the maximum capacity at
continuous speeds above 75 mph (120 km/h). WARNING!
Combining radial ply tires with other types of tires on
your vehicle will cause your vehicle to handle poorly.
The instability could cause a collision. Always use radial
ply tires in sets of four. Never combine them with other
types of tires.

SERVICING AND MAINTENANCE 457
Run Flat Tires — If Equipped
Run Flat tires allow you the capability to drive 50 miles
(80 km) at 50 mph (80 km/h) after a rapid loss of inflation
pressure. This rapid loss of inflation is referred to as the Run
Flat mode. A Run Flat mode occurs when the tire inflation
pressure is of/or below 14 psi (96 kPa). Once a Run Flat tire
reaches the run flat mode it has limited driving capabilities
and needs to be replaced immediately. A Run Flat tire is not
repairable. When a run flat tire is changed after driving with
underinflated tire condition, please replace the TPM sensor
as it is not designed to be reused when driven under run flat
mode (14 psi (96 kPa)) condition.
NOTE:
TPM Sensor must be replaced after driving the vehicle on a
flat tire condition.
It is not recommended driving a vehicle loaded at full
capacity or to tow a trailer while a tire is in the run flat mode.
See the tire pressure monitoring section for more informa -
tion. Tire Spinning
When stuck in mud, sand, snow, or ice conditions, do not
spin your vehicle's wheels above 30 mph (48 km/h) or for
longer than 30 seconds continuously without stopping.
Refer to “Freeing A Stuck Vehicle” in “In Case Of Emer -
gency” for further information.
WARNING!
Fast spinning tires can be dangerous. Forces generated
by excessive wheel speeds may cause tire damage or
failure. A tire could explode and injure someone. Do not
spin your vehicle's wheels faster than 30 mph (48 km/h)
for more than 30 seconds continuously when you are
stuck, and do not let anyone near a spinning wheel, no
matter what the speed.
7

458 SERVICING AND MAINTENANCE
Tread Wear Indicators
Tread wear indicators are in the original equipment tires to
help you in determining when your tires should be replaced.
Tire Tread
These indicators are molded into the bottom of the tread
grooves. They will appear as bands when the tread depth
becomes a 1/16 of an inch (1.6 mm). When the tread is worn
to the tread wear indicators, the tire should be replaced. Refer to “Replacement Tires” in this section for further infor -
mation.
Life Of Tire
The service life of a tire is dependent upon varying factors
including, but not limited to:
• Driving style.
• Tire pressure - Improper cold tire inflation pressures can
cause uneven wear patterns to develop across the tire
tread. These abnormal wear patterns will reduce tread life,
resulting in the need for earlier tire replacement.
• Distance driven.
• Performance tires, tires with a speed rating of V or higher,
and Summer tires typically have a reduced tread life. Rota -
tion of these tires per the vehicle scheduled maintenance is
highly recommended.1 — Worn Tire
2 — New Tire
WARNING!
Tires and the spare tire should be replaced after six
years, regardless of the remaining tread. Failure to follow
this warning can result in sudden tire failure. You could
lose control and have a collision resulting in serious
injury or death.

SERVICING AND MAINTENANCE 459
(Continued)NOTE:
Wheel Valve Stem must be replaced as well when installing
new tires due to wear and tear in existing tires.
Keep dismounted tires in a cool, dry place with as little expo -
sure to light as possible. Protect tires from contact with oil,
grease, and gasoline.
Replacement Tires
The tires on your new vehicle provide a balance of many
characteristics. They should be inspected regularly for wear
and correct cold tire inflation pressures. The manufacturer
strongly recommends that you use tires equivalent to the
originals in size, quality and performance when replacement
is needed. Refer to the paragraph on “Tread Wear Indica -
tors” in this section. Refer to the Tire and Loading Informa -
tion placard or the Vehicle Certification Label for the size
designation of your tire. The Load Index and Speed Symbol
for your tire will be found on the original equipment tire
sidewall.
See the Tire Sizing Chart example found in the “Tire Safety
Information” section of this manual for more information
relating to the Load Index and Speed Symbol of a tire. It is recommended to replace the two front tires or two rear
tires as a pair. Replacing just one tire can seriously affect
your vehicle’s handling. If you ever replace a wheel, make
sure that the wheel’s specifications match those of the orig -
inal wheels.
It is recommended you contact an authorized tire dealer or
original equipment dealer with any questions you may have
on tire specifications or capability. Failure to use equivalent
replacement tires may adversely affect the safety, handling,
and ride of your vehicle.
WARNING!
• Do not use a tire, wheel size, load rating, or speed rating
other than that specified for your vehicle. Some combi -
nations of unapproved tires and wheels may change
suspension dimensions and performance characteris -
tics, resulting in changes to steering, handling, and
braking of your vehicle. This can cause unpredictable
handling and stress to steering and suspension compo -
nents. You could lose control and have a collision
resulting in serious injury or death. Use only the tire
and wheel sizes with load ratings approved for your
vehicle. 7