2012 Ram 5500 Chassis Cab wheel size

Wind Buffeting
Wind buffeting can be described as the perception of
pressure on the ears or a helicopter-type sound in the
ears. Your vehicle may exhibit wind buffeting with the
windows down or in partially open positions. This is a
normal occurrence and can be minimized. If the rear
windows are open and buffeting occurs, open the front
and rear windows together to minimize the buffeting.
OCCUPANT RESTRAINTS
Some of the most important safety features in your
vehicle are the restraint systems:
•Three-point lap and shoulder belts for the driver and
all passengers
•Advanced Front Air Bags for driver and front passen-
ger — if equipped
•An energy-absorbing steering column and steering
wheel
•Knee bolsters/blockers for front seat occupants
•All seat belt systems (except driver ’s regular/Crew
Cab, first and second row center position for Crew
Cabonly) include Automatic Locking Retractors
(ALR)
If you will be carrying children too small for adult-sized
seat belts, the seat belts or the Lower Anchors and Tether
for CHildren (LATCH) feature also can be used to hold
infant and child restraint systems. For further informa-
tion, refer to “Lower Anchors and Tether for CHildren
(LATCH)”.
NOTE:The Advanced Front Air Bags have a multistage
inflator design. This allows the air bag to have different
rates of inflation based on the severity and type of
collision.
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THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 39

WARNING!
Ignoring the Air Bag Warning Light in your instru-
ment panel could mean you won’t have the air bags
to protect you in a collision. If the light does not come
on as a bulb check when the ignition is first turned
on, stays on after you start the vehicle, or if it comes
on as you drive, have an authorized dealer service the
air bag system immediately.
Driver And Passenger Advanced Front Air Bag
Inflator Units
The Driver and Passenger Advanced Front Air Bag
Inflator Units are located in the center of the steering
wheel and on the right side of the instrument panel (if
equipped). When the ORC detects a collision requiringthe Advanced Front Air Bags, it signals the inflator units.
A large quantity of non-toxic gas is generated to inflate
the Advanced Front Air Bags. Different air bag inflation
rates are possible, based on the collision type and sever-
ity. The steering wheel hub trim cover and the upper
right side of the instrument panel separate and fold out
of the way as the air bags inflate to their full size. The air
bags fully inflate in about 50 to 70 milliseconds. This is
about half of the time it takes to blink your eyes. The air
bags then quickly deflate while helping to restrain the
driver and front passenger.
The Advanced Front Air Bag gas is vented through the
vent holes in the sides of the air bag. In this way, the air
bags do not interfere with your control of the vehicle.
60 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE

▫Spare Tire Matching Original Equipped Tire
And Wheel – If Equipped.............. 330
▫Compact Spare Tire – If Equipped........ 331
▫Full Size Spare – If Equipped............ 332
▫Limited-Use Spare – If Equipped......... 332
▫TireSpinning ....................... 333
▫Tread Wear Indicators................. 333
▫LifeOfTire ........................ 334
▫Replacement Tires.................... 334
Supplemental Tire Pressure Information —
If Equipped.......................... 336
Tire Chains.......................... 336
Snow Tires.......................... 338Tire Rotation Recommendations........... 339
▫Dual Rear Wheels.................... 340
Fuel Requirements..................... 341
▫Reformulated Gasoline................ 342
▫Gasoline/Oxygenate Blends............. 342
▫E-85 Usage In Non-Flex Fuel Vehicles...... 342
▫MMT In Gasoline.................... 343
▫Materials Added To Fuel............... 344
▫Fuel System Cautions................. 344
▫Carbon Monoxide Warnings............ 345
Adding Fuel......................... 346
▫Loose Fuel Filler Cap Message........... 347
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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 temperatures.
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:
2H
Rear-Wheel Drive High Range - This range is for normal
street and highway driving on dry hard surfaced roads.
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STARTING AND OPERATING 295

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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Radial Ply Tires
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 result-
ing in serious injury or death. Always use radial ply
tires in sets of four (or six, in case of trucks with dual
rear wheels). Never combine them with other types
of tires.
Cuts and punctures in radial tires are repairable only in
the tread area because of sidewall flexing. Consult your
authorized tire dealer for radial tire repairs.
Spare Tire Matching Original Equipped Tire And
Wheel – If Equipped
Your vehicle may be equivalent with a spare tire and
wheel in look and function as the original equipment tire
and wheel found on the front or rear axle of your vehicle.
This spare tire may be used in the tire rotation for your
vehicle. If your vehicle has this option refer to an
authorized tire dealer for the recommended tire rotation
pattern.
If your vehicle is not equipped with an original equip-
ment tire and wheel as a spare, a non-matching tempo-
rary emergency use spare may be equipped with your
vehicle. Temporary use spares are engineered to be used
only with your vehicle. Your vehicle may be equipped
with one of the following types of non-matching tempo-
rary use spares; compact, full size, or limited-use. Do not
install more than one non-matching temporary use spare
tire/wheel on the vehicle at any given time.
330 STARTING AND OPERATING

CAUTION!
Because of the reduced ground clearance, do not take
your vehicle through an automatic car wash with a
compact, full size or limited-use temporary spare
installed. Damage to the vehicle may result.
Compact Spare Tire – If Equipped
The compact spare is for temporary emergency use only.
You can identify if your vehicle is equipped with a
compact spare by looking at the spare tire description on
the Tire and Loading Information Placard located on the
driver ’s side door opening or on the sidewall of the tire.
Compact spare tire descriptions begin with the letter “T”
or “S” preceding the size designation. Example: T145/
80D18 103M.
T, S = Temporary Spare TireSince this tire has limited tread life the original equip-
ment tire should be repaired (or replaced) and reinstalled
on your vehicle at the first opportunity.
Do not install a wheel cover or attempt to mount a
conventional tire on the compact spare wheel, since the
wheel is designed specifically for the compact spare tire.
Do not install more than one compact spare tire and
wheel on the vehicle at any given time
WARNING!
Compact spares are for temporary emergency use
only. With these spares, do not drive more than
50 mph (80 km/h). Temporary use spares have limited
tread life. When the tread is worn to the tread wear
indicators, the temporary use spare tire needs to be
replaced. Be sure to follow the warnings, which
apply to your spare. Failure to do so could result in
spare tire failure and loss of vehicle control.
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STARTING AND OPERATING 331

Full Size Spare – If Equipped
The full size spare is for temporary emergency use only.
This tire may look like the original equipped tire on the
front or rear axle of your vehicle, but it is not. This spare
tire may have limited tread life. When the tread is worn
to the tread wear indicators, the temporary use full size
spare tire needs to be replaced. Since it is not the same as
your original equipment tire, replace (or repair) the
original equipment tire and reinstall on the vehicle at the
first opportunity.
Limited-Use Spare – If Equipped
The limited-use spare tire is for temporary emergency
use only. This tire is identified by a label located on the
limited-use spare wheel. This label contains the driving
limitations for this spare. This tire may look like the
original equipped tire on the front or rear axle of your
vehicle, but it is not. Installation of this limited-use spare
tire affects vehicle handling. Since it is not the same asyour original equipment tire, replace (or repair) the
original equipment tire and reinstall on the vehicle at the
first opportunity.
WARNING!
Limited-use spares are for emergency use only. In-
stallation of this limited-use spare tire affects vehicle
handling. With this tire, do not drive more than the
speed listed on the limit-use spare wheel. Keep
inflated to the cold tire inflation pressure listed on
your Tire and Loading Information Placard located
on the driver ’s side door opening. Replace (or repair)
the original equipment tire at the first opportunity
and reinstall it on your vehicle. Failure to do so could
result in loss of vehicle control.
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