2008 DODGE RAM 2500 GAS air condition

Tire pressures change by approximately 1 psi (7 kPa) per
12ÉF (7ÉC) of air temperature change. Keep this in mind
when checking tire pressure inside a garage, especially in
the Winter.
Example: If garage temperature = 68ÉF (20ÉC) and the
outside temperature = 32ÉF (0ÉC) then the cold tire
inflation pressure should be increased by 3 psi (21 kPa),
which equals 1 psi (7 kPa) for every 12ÉF (7ÉC) 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
within posted speed limits. Where speed limits or condi-
tions are such that the vehicle can be driven at high
speeds, maintaining correct tire inflation pressure is very
important. Increased tire pressure and reduced vehicleloading may be required for high-speed vehicle opera-
tion. Refer to original equipment or an authorized tire
dealer for recommended safe operating speeds, loading
and cold tire inflation pressures.
WARNING!
High speed driving with your vehicle under maxi-
mum load is dangerous. The added strain on your
tires could cause them to fail. You could have a
serious accident. Don't drive a vehicle loaded to the
maximum capacity at continuous speeds above 75
mph (120 km/h).
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for optimum performance. The use of premium gasoline
is not recommended. Under normal conditions, the use of
premium gasoline will not provide a benefit over high-
quality regular and mid-grade gasolines, and in some
circumstances may result in poorer performance.
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 ªregularº 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, performanceand durability for your vehicle. We recommend the use
of gasolines that meet the WWFC specifications if they
are available.
Reformulated Gasoline
Many areas of the country require the use of cleaner
burning gasoline referred to as ªReformulated Gasolineº
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.
372 STARTING AND OPERATING

allowed in the United States. MMT is prohibited in
Federal and California reformulated gasoline.
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:
²The use of leaded gas is prohibited by Federal law.
Using leaded gasoline can impair engine performance,
damage the emission control system.
²An 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.
²When 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 persists, lighten the load,
or engine piston damage may result.
²The use of fuel additives which are now being sold as
octane enhancers is not recommended. Many of these
products contain high concentrations of methanol.
Fuel system damage or vehicle performance problems
resulting from the use of such fuels or additives is not
the responsibility of the manufacturer.
374 STARTING AND OPERATING

NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
Carbon Monoxide Warnings
WARNING!
Carbon monoxide (CO) in exhaust gases is deadly.
Follow the precautions below to prevent carbon
monoxide poisoning:
²Do not inhale exhaust gases. They contain carbon
monoxide, a colorless and odorless gas which can kill.
Never run the engine in a closed area, such as a
garage, and never sit in a parked vehicle with the
engine running for an extended period. If the vehicle is
stopped in an open area with the engine running formore than a short period, adjust the ventilation system
to force fresh, outside air into the vehicle.
²Guard against carbon monoxide with proper mainte-
nance. Have the exhaust system inspected every time
the vehicle is raised. Have any abnormal conditions
repaired promptly. Until repaired, drive with all side
windows fully open.
²Keep the liftgate closed when driving your vehicle to
prevent carbon monoxide and other poisonous ex-
haust gases from entering the vehicle.
ADDING FUEL
Adding Fuel (Gas Engines)
The fuel tank filler tube has a restricting door about 2 in
(50 mm) inside the opening. If using a portable fuel
container, it should have a flexible nozzle long enough to
force open the restricting door.
STARTING AND OPERATING 375
5

þAir Conditioning
Turn off temporarily.
þrefer to Cooling System Operating information in the
Maintenance section of this manual for more informa-
tion.
Trailer Towing Mirrors Ð If Equipped
These mirrors are designed with an adjustable mirror
head to provide a greater vision range when towing
extra-wide loads. To change position inboard or out-
board, the mirror head should be rotated (flipped Out or
In). A small blindspot mirror is integrated onto the main
mirror surface.
NOTE: Fold the7x10inch trailer towing mirrors
rearward prior to entering an automated car wash.
Blindspot Mirror
400 STARTING AND OPERATING

necessary at the beginning and end of the snowplow
season. This will help prevent uneven tire wear.
The blade should be lowered whenever the vehicle is
parked.
Maintain and operate your vehicle and snowplow equip-
ment following the recommendations provided by the
specific snowplow manufacturer.
Over the Road Operation With Snowplow
Attached
The blade restricts airflow to the radiator and causes the
engine to operate at higher than normal temperatures.
Therefore, when transporting the plow, angle the blade
completely and position it as low as road or surface
conditions permit. Do not exceed 40 mph (64 km/h). The
operator should always maintain a safe stopping distance
and allow adequate passing clearance.
Methods For Removing Snow
Operating Tips
Under ideal snow plowing conditions, 20 mph (32 km/h)
should be maximum operating speed. The operator
should be familiar with the area and surface to be
cleaned. Reduce speed and use extreme caution when
plowing unfamiliar areas or under poor visibility.
404 STARTING AND OPERATING

MAINTAINING YOUR VEHICLE
CONTENTS
mEngine CompartmentÐ 3.7L...............444
mEngine CompartmentÐ 4.7L...............445
mEngine CompartmentÐ 5.7L...............446
mOnboard Diagnostic System (OBD II).........447
NLoose Fuel Filler Cap Message............447
mEmissions Inspection And Maintenance
Programs............................448
mReplacement Parts......................449
mAuthorized Dealer Service................450mMaintenance Procedures..................450
NEngine Oil..........................451
NEngine Oil Filter......................454
NDrive Belts Ð Check Condition And Tension . . 454
NSpark Plugs (Gas Engines)...............454
NEngine Air Cleaner Filter................455
NEngine Fuel Filter.....................455
NCatalytic Converter....................455
NEmission-Related Components............457
7

NMaintenance-Free Battery................457
NAir Conditioner Maintenance.............459
NPower Steering Ð Fluid Check............460
NFront Suspension Ball Joints..............460
NSteering Linkage Ð Inspection............461
NHalf-Shaft Constant Velocity Joints.........461
NFront Prop Shaft Lubrication Ð
2500/3500 (4X4) Models................462
NBody Lubrication.....................462
NWindshield Wiper Blades................463
NWindshield Washers...................463
NExhaust System......................464NCooling System.......................465
NHoses And Vacuum/Vapor Harnesses.......470
NFuel System Connections................471
NBrake System........................471
NClutch Hydraulic System................474
NClutch Linkage.......................474
NRear Axle And 4X4 Front Driving Axle
Fluid Level..........................474
NTransfer Case........................475
NManual Transmission..................476
NAutomatic Transmission................476
NFront And Rear Wheel Bearings...........479
442 MAINTAINING YOUR VEHICLE