RAM CHASSIS CAB 2012 Owners Manual
Manufacturer: RAM, Model Year: 2012, Model line: CHASSIS CAB, Model: RAM CHASSIS CAB 2012Pages: 502, PDF Size: 3.96 MB
Page 331 of 502

Information” placard 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 original wheels.
It is recommended you contact your original equipment
or an authorized tire 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 or rating other than
that specified for your vehicle. Some combinations
of unapproved tires and wheels may change sus-
pension dimensions and performance characteris-
tics, resulting in changes to steering, handling, and
braking of your vehicle. This can cause unpredict-
able handling and stress to steering and suspen-
sion 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.
(Continued)
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WARNING! (Continued)• 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 overloading and failure.
You could lose control and have a collision result-
ing in serious injury or death.
• Failure to equip your vehicle with tires having
adequate speed capability can result in sudden tire
failure and loss of vehicle control resulting in
serious injury or death.
CAUTION!Replacing original tires with tires of a different size
may result in false speedometer and odometer read-
ings. SUPPLEMENTAL TIRE PRESSURE INFORMATION
— IF EQUIPPED
A light load vehicle condition is defined as two passen-
gers [150 lbs (68 kg) each] plus 200 lbs (91 kg) of cargo.
Cold tire inflation pressures for a lightly loaded vehicle
will be found on the face of the driver’s door.
TIRE CHAINS
Use “Class U” chains or other traction aids that meet SAE
Type “U” specifications.
NOTE: Chains must be the proper size for the vehicle,
as recommended by the chain manufacturer.
CAUTION!To avoid damage to your vehicle, tires or chains,
observe the following precautions:
(Continued)330 STARTING AND OPERATING
Page 333 of 502

CAUTION! (Continued)• Because of limited chain clearance between tires
and other suspension components, it is important
that only chains in good condition are used. Bro-
ken chains can cause serious vehicle damage. Stop
the vehicle immediately if noise occurs that could
suggest chain breakage. Remove the damaged
parts of the chain before further use.
• Install chains as tightly as possible and then
retighten after driving about 1/2 mi (0.8 km).
• Do not exceed 45 mph (72 km/h).
• Drive cautiously and avoid severe turns and large
bumps, especially with a loaded vehicle.
• Do not install tire chains on front wheels of 4x2
vehicles.
• Do not drive for a prolonged period on dry pave-
ment.
(Continued) CAUTION! (Continued)• Observe the tire chain manufacturer’s instructions
on method of installation, operating speed, and
conditions for usage. Always use the lower sug-
gested operating speed of the chain manufacturer
if different than the speed recommended by the
manufacturer.
These cautions apply to all chain traction devices, includ-
ing link and cable (radial) chains.
Tire chain use is permitted only on the rear tires of your
4X2 trucks.
NOTE:
• The use of class “U” chains is permitted on the front
and rear of 4X4 vehicles, trucks with dual rear wheels
and LT235/80R17 tires.
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• On 4X2 vehicles, class “U” snow chains are permitted
on the rear wheels only of vehicles equipped with
LT245/70R17, LT265/70R17, and LT235/80R17 size
tires.
• On 4X4 Single Rear Wheel (SRW) vehicles, class “U”
snow chains are permitted on the rear wheels only on
vehicles equipped with LT265/70R17.
CAUTION!Do not use tire chains on the 4X2 front wheels of
SRW (Single Rear Wheels) equipped with LT245/
70R17, LT265/70R17 tires or 4X4 front tires of vehicles
equipped with LT265/70R17 tires. There may not be
adequate clearance for the chains and you are risking
structural or body damage to your vehicle. SNOW TIRES
Some areas of the country require the use of snow tires
during the winter. All season tires can be identified by the
M+S designation on the tire sidewall.
If you need snow tires, select tires equivalent in size and
type to the original equipment tires. Use snow tires only
in sets of four; failure to do so may adversely affect the
safety and handling of your vehicle.
Snow tires generally have lower speed ratings than what
was originally equipped with your vehicle and should
not be operated at sustained speeds over 75 mph
(120 km/h). For speeds above 75 mph (120 km/h) refer to
original equipment or an authorized tire dealer for
recommended safe operating speeds, loading and cold
tire inflation pressures.332 STARTING AND OPERATING
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While studded tires improve performance on ice, skid
and traction capability on wet or dry surfaces may be
poorer than that of non-studded tires. Some states pro-
hibit studded tires; therefore, local laws should be
checked before using these tire types.
TIRE ROTATION RECOMMENDATIONS
Tires on the front and rear axles of vehicles operate at
different loads and perform different steering, driving,
and braking functions. For these reasons, they wear at
unequal rates.
These effects can be reduced by timely rotation of tires.
The benefits of rotation are especially worthwhile with
aggressive tread designs such as those on On/Off Road
type tires. Rotation will increase tread life, help to main-
tain mud, snow, and wet traction levels, and contribute to
a smooth, quiet ride. Refer to the “Maintenance Schedule” for the proper
maintenance intervals. More frequent rotation is permis-
sible if desired. The reasons for any rapid or unusual
wear should be corrected prior to rotation being per-
formed.
Tire Rotation
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NOTE: On Canadian vehicles only, if your vehicle is
equipped with All-Season type tires on the front and
On/Off Road type tires mounted on the rear, do not use
a front to back rotation pattern. Instead, rotate your tires
side to side at the recommended intervals.
Dual Rear Wheels The tires used on dual wheel assemblies should be
matched for wear to prevent overloading one tire in a set.
To check if tires are even, lay a straight edge across all
four tires. The straight edge should touch all the tires.
CAUTION!4500/5500 Dual Rear Tires have only one approved
direction of rotation. This is to accommodate the
asymmetrical design (tread pattern) of the On/Off
road tire.
(Continued)
Tire Rotation334 STARTING AND OPERATING
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CAUTION! (Continued)• When replacing a flat, the spare tire may have to
be remounted on the rim or installed at a different
location to maintain the correct placement of the
tire on the wheel relative to the tire/wheel position
on the vehicle. For example, if the spare is used to
replace an outer rear tire it will have to be re-
mounted on the rim so that the wheel is dished
inward. That way the tread design of asymmetrical
tires will maintain proper position.
FUEL REQUIREMENTS
The 5.7L engine is designed to meet all
emissions regulations and provide satisfac-
tory fuel economy and performance when
using high-quality unleaded gasoline hav-
ing an octane range of 87 to 89. The manu-
facturer recommends the use of 89 octane for optimum performance. The use of premium gasoline
is not recommended, as it will not provide any benefit
over regular gasoline in these engines.
Light spark knock at low engine speeds is not harmful to
your engine. However, continued heavy spark knock at
high speeds can cause damage and immediate service is
required.
Poor quality gasoline can cause problems such as hard
starting, stalling and hesitations. If you experience these
symptoms, try another brand of “regular” gasoline be-
fore considering service for the vehicle.
Over 40 auto manufacturers worldwide have issued and
endorsed consistent gasoline specifications (the World-
wide Fuel Charter, WWFC) to define fuel properties
necessary to deliver enhanced emissions, performance
and durability for your vehicle. We recommend the use
of gasolines that meet the WWFC specifications if they
are available. 5 STARTING AND OPERATING 335
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Reformulated Gasoline
Many areas of the country require the use of cleaner
burning gasoline referred to as “Reformulated Gasoline”
Reformulated gasolines contain oxygenates, and are spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.
The manufacturer supports the use of reformulated gaso-
lines. Properly-blended reformulated gasolines will pro-
vide excellent performance and durability of engine and
fuel system components.
Gasoline/Oxygenate Blends
Some fuel suppliers blend unleaded gasoline with oxy-
genates such as 10% ethanol, MTBE, and ETBE. Oxygen-
ates are required in some areas of the country during the
Winter months to reduce carbon monoxide emissions.
Fuels blended with these oxygenates may be used in
your vehicle. CAUTION!Do not use gasolines containing Methanol or E-85
Ethanol. Use of these blends may result in starting
and drivability problems and may damage critical
fuel system components.
Problems that result from using methanol/gasoline or
E-85 Ethanol blends are not the responsibility of the
manufacturer. While MTBE is an oxygenate made from
Methanol, it does not have the negative effects of
Methanol.
E-85 Usage In Non-Flex Fuel Vehicles
Non-FFV vehicles are compatible with gasoline contain-
ing 10% ethanol (E10). Gasoline with higher ethanol
content may void the vehicle’s warranty.336 STARTING AND OPERATING
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If a Non-FFV vehicle is inadvertently fueled with E-85
fuel, the engine will have some or all of these symptoms:
• operate in a lean mode
• OBD II “Malfunction Indicator Light” on
• poor engine performance
• poor cold start and cold drivability
• increased risk for fuel system component corrosion
To fix a Non-FFV vehicle inadvertently fueled once with
E-85 perform the following:
• drain the fuel tank (see your authorized dealer)
• change the engine oil and oil filter
• disconnect and reconnect the battery to reset the
engine controller memory More extensive repairs will be required for prolonged
exposure to E-85 fuel.
MMT In Gasoline
MMT is a manganese containing metallic additive that is
blended into some gasoline to increase octane. Gasoline
blended with MMT provides no performance advantage
beyond gasoline of the same octane number without
MMT. Gasoline blended with MMT reduces spark plug
life and reduces emission system performance in some
vehicles. The manufacturer recommends that gasoline
without MMT be used in your vehicle. The MMT content
of gasoline may not be indicated on the gasoline pump,
therefore, you should ask your gasoline retailer whether
or not the gasoline contains MMT. It is even more
important to look for gasolines without MMT in Canada,
because MMT can be used at levels higher than those
allowed in the United States. MMT is prohibited in
Federal and California reformulated gasoline.
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Materials Added To Fuel
All gasolines sold in the United States are required to
contain effective detergent additives. Use of additional
detergents or other additives is not needed under normal
conditions and would result in unnecessary cost. There-
fore, you should not have to add anything to the fuel.
Fuel System Cautions
CAUTION!Follow these guidelines to maintain your vehicle’s
performance:
• The use of leaded gas is prohibited by Federal law.
Using leaded gasoline can impair engine perfor-
mance, damage the emission control system.
(Continued) CAUTION! (Continued)• An out-of-tune engine, or certain fuel or ignition
malfunctions, can cause the catalytic converter to
overheat. If you notice a pungent burning odor or
some light smoke, your engine may be out of tune
or malfunctioning and may require immediate
service. Contact your authorized dealer for service
assistance.
• When pulling a heavy load or driving a fully-
loaded vehicle when the humidity is low and the
temperature is high, use a premium unleaded fuel
to help prevent spark knock. If spark knock per-
sists, lighten the load, or engine piston damage
may result.
(Continued)338 STARTING AND OPERATING