2012 RAM CHASSIS CAB tire size

▫ Compact Spare Tire – If Equipped ........ 325
▫ Full Size Spare – If Equipped ............ 326
▫ Limited-Use Spare – If Equipped ......... 326
▫ Tire Spinning ....................... 327
▫ Tread Wear Indicators ................. 327
▫ Life Of Tire ........................ 328
▫ Replacement Tires .................... 328
 Supplemental Tire Pressure Information — If
Equipped ............................ 330
 Tire Chains .......................... 330
 Snow Tires .......................... 332
 Tire Rotation Recommendations ........... 333
▫ Dual Rear Wheels .................... 334  Fuel Requirements ..................... 335
▫ Reformulated Gasoline ................ 336
▫ Gasoline/Oxygenate Blends ............. 336
▫ E-85 Usage In Non-Flex Fuel Vehicles ...... 336
▫ MMT In Gasoline .................... 337
▫ Materials Added To Fuel ............... 338
▫ Fuel System Cautions ................. 338
▫ Carbon Monoxide Warnings ............ 339
 Adding Fuel ......................... 340
▫ Loose Fuel Filler Cap Message ........... 341
 Vehicle Loading ...................... 342
▫ Certification Label ................... 342
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When operating your vehicle in 4L, the engine speed is
approximately three times that of the 2H or 4H 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 will adversely affect shifting and
can cause damage to the drivetrain.
NOTE: Do not attempt to make a shift while only the
front or rear wheels are spinning. The transfer case is not
equipped with a synchronizer and therefore the front and
rear driveshaft speeds must be equal for the shift to take
place. Shifting while only the front or rear wheels are
spinning can cause damage to the transfer case.
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. NOTE: Delayed shifts out of four-wheel drive may be
experienced due to uneven tire wear, low or uneven tire
pressures, excessive vehicle loading, or cold tempera-
tures.
WARNING!You or others could be injured if you leave the
vehicle unattended with the transfer case in the
NEUTRAL position without first fully engaging the
parking brake. The transfer case NEUTRAL position
disengages both the front and rear driveshafts from
the powertrain and will allow the vehicle to move
regardless of the transmission position. The parking
brake should always be applied when the driver is
not in the vehicle.
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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.
WARNING!You or others could be injured if you leave the
vehicle unattended with the transfer case in the
NEUTRAL position without first fully engaging the
parking brake. The transfer case NEUTRAL position
disengages both the front and rear driveshafts from
the powertrain and will allow the vehicle to move
regardless of the transmission position. The parking
brake should always be applied when the driver is
not in the vehicle. For additional information on the appropriate use of each
transfer case mode position, see the information below:
2WD
Rear Wheel Drive High Range - This range is for normal
street and highway driving on dry, hard surfaced roads.
4WD LOCK
Four-Wheel Drive Lock Range - This range locks the front
and rear driveshafts together forcing the front and rear
wheels to rotate at the same speed. This range provides
additional traction for loose, slippery road surfaces only.
4WD LOW
Four-Wheel Drive Low Range - This range provides low
speed four-wheel drive. It locks the front and rear
driveshafts together forcing the front and rear wheels to
rotate at the same speed. This range provides additional
traction and maximum pulling power for loose, slippery
road surfaces only. Do not exceed 25 mph (40 km/h).
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TIRE SAFETY INFORMATION
Tire Markings NOTE:
• 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 designa-
tion. 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  P  is 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 preced-
ing the size designation. Example: LT235/85R16.
• Temporary spare tires are spares designed for tempo-
rary emergency use only. Temporary high pressure1 — 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
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compact spare tires have the letter “T” or “S” molded
into the sidewall preceding the size designation. Ex-
ample: T145/80D18 103M. • High flotation tire sizing is based on U.S. design
standards and it begins with the tire diameter molded
into the sidewall. Example: 31x10.5 R15 LT.
Tire Sizing Chart
EXAMPLE:
Size Designation:
P = Passenger car tire size based on U.S. design standards
 ....blank....  = Passenger car tire based on European design standards
LT = Light truck tire based on U.S. design standards
TorS = Temporary spare tire
31 = Overall diameter in inches (in)
215 = Section width in millimeters (mm)
65 = Aspect ratio in percent (%)
— Ratio of section height to section width of tire
10.5 = Section width in inches (in)
R = Construction code
—  R  means radial construction
—  D  means diagonal or bias construction
15 = Rim diameter in inches (in)310 STARTING AND OPERATING

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.
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 1991312 STARTING AND OPERATING

Tire Terminology And Definitions
Term Definition
B-Pillar The 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 3 hours, or driven less
than 1 mile (1.6 km) after sitting for a three hour period. 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 pres-
sure 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 paper 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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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 and in the “Vehicle Loading” 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 this section.
To determine the maximum loading conditions of your
vehicle, locate the statement “The combined weight of
occupants and cargo should never exceed XXX lbs or
XXX kg” 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 occu-
pants and cargo should never exceed XXX lbs or XXX kg”
on your vehicle’s placard.
2. Determine the combined weight of the driver and
passengers that will be riding in your vehicle.
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