tire size RAM PROMASTER 2023 User Guide

162SAFETY
Trailer Merge Assist — If Equipped
Trailer Merge Assist is a function of the Blind Spot
Monitoring (BSM) system that extends the blind
spot zone to work while pulling a trailer.
NOTE:When Trailer Merge Assist is activated, Rear Cross
Path is disabled.
Trailer Merge Assist consists of three sub
functions:
Automatic Trailer Detection
Trailer Length Detection
Trailer Merge Warning

Blind Spot Zones With Trailer Merge Assist
Automatic Trailer Detection
There are two modes of operation for the detection
of the trailer length:
Automatic Mode
— When “Auto Mode” is
selected, the system will use the blind spot
sensors to automatically determine the pres -
ence and length of a trailer. The presence of a
trailer will be detected using the blind spot radar
within 90 seconds of forward movement of the
vehicle. The vehicle must be moving above
6 mph (10 km/h) to activate the feature. Once
the trailer has been detected, the system will
default to the maximum blind spot zone until the
length has been verified. You will see “Auto” in
the instrument panel cluster .
Maximum Mode — When “Max Mode” is
selected, the system will default to the
maximum blind spot zone regardless of what
size trailer is attached .
NOTE:Selected setting is stored when the ignition is
placed in the OFF position. To change this setting,
it must be selected through the Uconnect Settings
Ú page 134. Trailer Length Detection
Once the trailer presence has been established,
the trailer length will be established (by making a
90 degree turn) and then the trailer length
category (example 10-20 ft (3 m to 6 m)) will be
displayed. This can take up to 30 seconds after
completing the turn.
NOTE:During the same ignition cycle, if the vehicle is at a
standstill for a minimum of 90 seconds, a new
“trailer detection request” is enabled by the
system once the vehicle resumes motion.
The maximum trailer length supported by the
Trailer Merge Assist feature is 39.5 ft (12 m).
Trailer length is considered the forward most
portion of the trailer hitch to the rearward most
portion of the body, fascia/bumper, or ramp of
the trailer.
The maximum width supported by the Trailer
Merge Assist feature is 8.5 ft (2.59 m). Trailer
width is measured at the widest portion of the
trailer and may include wheels, tires, finders,
or rails.
1 — Vehicle
2 — Trailer

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SAFETY169
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 pressure
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 effi -
ciency 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 responsibility
to maintain correct tire pressure using an accu -
rate 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 280.
Base System
This is the TPMS Warning Light 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 System 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.
CAUTION!

The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures and
warning have been established 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 pressure
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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170SAFETY
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.
Here are some simple steps you can take to
minimize the risk of harm from a deploying air bag:

1. Children 12 years old and under should
always ride buckled up in the rear seat of a
vehicle with a rear seat.

2. A child who is not big enough to wear the vehicle seat belt properly must be secured in the
appropriate child restraint or belt-positioning
booster seat in a rear seating position

Ú
page 185.

3. If a child from 2 to 12 years old (not in a rear-facing child restraint) must ride in the
front passenger seat, move the seat as far
back as possible and use the proper child
restraint Ú page 185.
4. Never allow children to slide the shoulder belt behind them or under their arm.

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SERVICING AND MAINTENANCE249
3. Remove and replace the bulbs as needed.

Dome Lamp Light Bulbs

4. Close the housing cover making sure it snaps together properly and connect the lamp.
5. Install overhead console into place making sure to seat the assembly’s forward end first
and then snapping it flush so that the tension
spring is fully seating in the housing.
TIRES
TIRE SAFETY INFORMATION
Tire safety information will cover aspects of
the following information: Tire Markings, Tire
Identification Numbers, Tire Terminology and
Definitions, Tire Pressures, and Tire Loading.
Tire Markings

Tire Markings

NOTE:
P (Passenger) — Metric tire sizing is based on US
design standards. P-Metric tires have the letter
“P” molded into the sidewall preceding the size
designation. Example: P215/65R15 95H.
European — Metric tire sizing is based on Euro -
pean design standards. Tires designed to this
standard have the tire size molded into the side -
wall beginning with the section width. The letter
"P" is absent from this tire size designation.
Example: 215/65R15 96H.
LT (Light Truck) — Metric tire sizing is based on
US design standards. The size designation for
LT-Metric tires is the same as for P-Metric tires
except for the letters “LT” that are molded into
the sidewall preceding the size designation.
Example: LT235/85R16.
Temporary spare tires are designed for tempo -
rary emergency use only. Temporary high pres -
sure compact spare tires have the letter “T” or
“S” molded into the sidewall preceding the size
designation. Example: T145/80D18 103M.
High flotation tire sizing is based on US design
standards and it begins with the tire diameter
molded into the sidewall. Example: 31x10.5
R15 LT.
1 — US DOT Safety Standards
Code (TIN)
2 — Size Designation
3 — Service Description
4 — Maximum Load
5 — Maximum Pressure
6 — Treadwear, Traction and
Temperature Grades
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250SERVICING AND MAINTENANCE
TIRE SIZING CHART
EXAMPLE:
Example Size Designation: P215/65R15XL 95H, 215/65R15 96H, LT235/85R16C, T145/80D18 103M, 31x10.5 R15 LT
P = Passenger car tire size based on US design standards, or
"....blank...." = Passenger car tire based on European design standards, or
LT = Light truck tire based on US design standards, or
T or S = Temporary spare tire or
31 = Overall diameter in inches (in)
215, 235, 145 = Section width in millimeters (mm)
65, 85, 80 = Aspect ratio in percent (%)
Ratio of section height to section width of tire, or
10.5 = Section width in inches (in)
R = Construction code
"R" means radial construction, or
"D" means diagonal or bias construction
15, 16, 18 = Rim diameter in inches (in)
Service Description:
95 = Load Index
A numerical code associated with the maximum load a tire can carry
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)

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SERVICING AND MAINTENANCE251
Tire Identification Number (TIN)
The TIN may be found on one or both sides of the tire; however, the date code may only be on one side. Tires with white sidewalls will have the full TIN, including
the date code, located on the white sidewall side of the tire. Look for the TIN on the outboard side of black sidewall tires as mounted on the vehicle. If the TIN is
not found on the outboard side, then you will find it on the inboard side of the tire.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:
EXAMPLE:
DOT MA L9 ABCD 0301
DOT = Department of Transportation
This symbol certifies that the tire is in compliance with the US Department of Transportation tire safety standards and is approved for highway use
MA = Code representing the tire manufacturing location (two digits)
L9 = Code representing the tire size (two digits)
ABCD = Code used by the tire manufacturer (one to four digits)8

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252SERVICING AND MAINTENANCE
Tire Terminology And Definitions
03 = Number representing the week in which the tire was manufactured (two digits)
03 means the 3rd week
01 = Number representing the year in which the tire was manufactured (two digits)
01 means the year 2001
Prior to July 2000, tire manufacturers were only required to have one number to represent the year in which the tire was manufactured. Example: 031 could
represent the 3rd week of 1981 or 1991
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 The manufacturers 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.
EXAMPLE:

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SERVICING AND MAINTENANCE253
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)

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
Úpage 123.
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 Ú page 123.
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.
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SERVICING AND MAINTENANCE257

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
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.
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, maintaining 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 authorized 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 (sidewall damage is not repairable).

The puncture is no greater than ¼ of an inch (6 mm).

Consult an authorized tire dealer for tire repairs
and additional information.
Damaged Run Flat tires, or Run Flat tires that have
experienced 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.
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 being driven under a Run Flat
mode 14 psi (96 kPa) condition, please replace the
TPMS sensor 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.

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SERVICING AND MAINTENANCE259
Keep dismounted tires in a cool, dry place with as
little exposure 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
using tires equivalent to the originals in size, quality
and performance when replacement is needed. Refer
to the paragraph on “Tread Wear Indicators” in this
section. Refer to the Tire And Loading Information
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 Ú page 250.
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 original 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.
TIRE TYPES
All Season Tires — If Equipped
All Season tires provide traction for all seasons
(Spring, Summer, Autumn, and Winter). Traction
levels may vary between different all season tires.
All season tires can be identified by the M+S, M&S,
M/S or MS designation on the tire sidewall. Use all
season tires only in sets of four; failure to do so
may adversely affect the safety and handling of
your vehicle.
Summer Or Three Season Tires —
If Equipped

Summer tires provide traction in both wet and dry
conditions, and are not intended to be driven in snow or
on ice. If your vehicle is equipped with Summer tires, be
aware these tires are not designed for Winter or cold
driving conditions. Install Winter tires on your vehicle
when ambient temperatures are less than 40°F (5°C)
or if roads are covered with ice or snow. For more
information, contact an authorized dealer.

WARNING!
Do not use a tire, wheel size, load rating, or
speed rating other than that specified for your
vehicle. Some combinations of unapproved
tires and wheels may change suspension
dimensions and performance characteristics,
resulting in changes to steering, handling, and
braking of your vehicle. This can cause unpre
-
dictable handling and stress to steering and
suspension components. 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.
Never use a tire with a smaller load index or
capacity, other than what was originally
equipped on your vehicle. Using a tire with a
smaller load index could result in tire over -
loading and failure. You could lose control and
have a collision.
Failure to equip your vehicle with tires having
adequate speed capability can result in
sudden tire failure and loss of vehicle control.
CAUTION!
Replacing original tires with tires of a different
size may result in false speedometer and
odometer readings.
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