2019 Ram 1500 tire size

The “SVC 4WD Warning Light” monitors the electronic
shift four-wheel drive system. If this light remains on after
engine start up or illuminates during driving, it means that
the four-wheel drive system is not functioning properly
and that service is required.
WARNING!
Always engage the parking brake when powering
down the vehicle if the “SVC 4WD Warning Light” is
illuminated. Not engaging the parking brake may
allow the vehicle to roll which may cause personal
injury or death.
NOTE: Do not attempt to make a shift while only the front
or rear wheels are spinning. This could cause damage to
driveline components.
When operating your vehicle in 4WD LOW, the engine
speed is approximately three times that of the 2WD, 4WD
AUTO or 4WD HIGH 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 in tire size can cause damage to the
drivetrain.
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.Shifting Procedure
NOTE:
•
If any of the requirements to select a new transfer case
position have not been met, the transfer case will not
shift. The position indicator light for the previous posi-
tion will remain ON and the newly selected position
indicator light will continue to flash until all the require-
ments for the selected position have been met.
•
If all the requirements to select a new transfer case
position have been met, the current position indicator
light will turn OFF, the selected position indicator light
will flash until the transfer case completes the shift. When
the shift is complete, the position indicator light for the
selected position will stop flashing and remain ON.
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WARNING!(Continued)
You should switch off the ACC system:
•When driving in fog, heavy rain, heavy snow, sleet,
heavy traffic, and complex driving situations (i.e., in
highway construction zones).
• When entering a turn lane or highway off ramp;
when driving on roads that are winding, icy, snow-
covered, slippery, or have steep uphill or downhill
slopes.
• When towing a trailer up or down steep slopes.
• When circumstances do not allow safe driving at a
constant speed.
Adaptive Cruise Control (ACC) Operation
The speed control buttons (located on the right side of the
steering wheel) operates the ACC system.
NOTE:Any chassis/suspension or tire size modifications
to the vehicle will effect the performance of the Adaptive
Cruise Control and Forward Collision Warning System.
Adaptive Cruise Control Buttons
1 — SET (+)/Accel 5 — CANC/Cancel
2 — Normal (Fixed Speed)
Cruise Control On/Off 6 — Distance Setting Decrease
3 — RES/Resume 7 — Adaptive Cruise Control
(ACC) On/Off
4 — SET (-)/Decel 8 — Distance Setting Increase
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STARTING AND OPERATING 345

2. Insert funnel into same filler pipe opening as the fuelnozzle.
3. Ensure funnel is inserted fully to hold flapper doors open.
4. Pour fuel into funnel opening.
5. Remove funnel from filler pipe, clean off prior to putting back in the jack and jack tool kit.
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 in-
creased durability does not necessarily increase the vehi-
cle’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.
406 STARTING AND OPERATING

WARNING!(Continued)
•Total weight must be distributed between the tow
vehicle and the trailer such that the following four
ratings are not exceeded:
1. GVWR
2. GTW
3. GAWR
4. Tongue weight rating for the trailer hitch utilized.
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 procedures.
• 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 proce-
dures. Replacing tires with a higher load carrying capac-
ity 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 inadequate braking and possible per-
sonal injury.
• An electronically actuated trailer brake controller is
required when towing a trailer with electronically actu-
ated 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).
416 STARTING AND OPERATING

Tire MarkingsNOTE:
•P (Passenger) — Metric tire sizing is based on U.S.
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 European
design standards. Tires designed to this standard have
the tire size molded into the sidewall beginning with the
section width. The letter Pis absent from this tire size
designation. Example: 215/65R15 96H.
• LT (Light Truck) — Metric tire sizing is based on U.S.
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 temporary emer-
gency use only. Temporary high pressure 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 U.S. design stan-
dards and it begins with the tire diameter molded into
the sidewall. Example: 31x10.5 R15 LT.
Tire Markings
1 — U.S. DOT Safety
Standards Code (TIN) 4 — Maximum Load
2 — Size Designation 5 — Maximum Pressure
3 — Service Description 6 — Treadwear, Traction and Temperature Grades 8
SERVICING AND MAINTENANCE 523

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 U.S. design standards, or
....blank.... = Passenger car tire based on European design standards, or
LT = Light truck tire based on U.S. design standards, or
TorS= 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
524 SERVICING AND MAINTENANCE

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 forthe 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.
EXAMPLE:
DOT MA L9 ABCD 0301
DOT = Department of Transportation
–This symbol certifies that the tire is in compliance with the U.S. 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)
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
526 SERVICING AND MAINTENANCE

Tire Terminology And Definitions
TermDefinition
B-Pillar The vehicle B-Pillar is the structural member of the body located be-
hind 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. In-
flation 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 recom-
mended cold tire inflation pressures.
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SERVICING AND MAINTENANCE 527