2008 DODGE RAM 3500 GAS check engine

5. Approximately 15 seconds later, one of two things will
happen:
a. The MIL will blink for approximately five seconds
and then remain on until the first engine crank or the
key is turned off. This means that your vehicle's OBD
system isnot readyand you shouldnotproceed to the
I/M station.
b. The MIL will remain fully illuminated until the first
engine crank or the key is turned off. This means that
your vehicle's OBD system isreadyand you can
proceed to the I/M station.
If your OBD system isnot ready,you should see your
authorized dealer or repair facility. If your vehicle was
recently serviced, or had a battery failure or replacement,
you may need to do nothing more than drive your
vehicle as you normally would in order for your OBD
system to update. A recheck with the above test routine
may then indicate that the system is now ready.Regardless of whether your vehicle's OBD system is
ready or not ready, if the MIL symbol is illuminated
during normal vehicle operation, you should have your
vehicle serviced before going to the I/M station. The I/M
station can fail your vehicle because the MIL symbol is on
with the engine running.
REPLACEMENT PARTS
Use of genuine Mopartparts for normal/scheduled
maintenance and repairs is highly recommended to en-
sure the designed performance. Damage or failures
caused by the use of non-Mopartparts for maintenance
and repairs will not be covered by the manufacturer's
warranty.
MAINTAINING YOUR VEHICLE 449
7

Engine Oil
Checking Oil Level
To assure proper lubrication of your vehicle's engine, the
engine oil must be maintained at the correct level. The
best time to check the engine oil level is about five
minutes after a fully warmed up engine is shut off or
before starting the engine after it has sat overnight.
Checking the oil while the vehicle is on level ground will
improve the accuracy of the oil level readings. Always
maintain the oil level within the SAFE zone on the
dipstick. Adding one quart of oil when the reading is at
the bottom of the SAFE zone will result in a reading at the
top of the safe zone on these engines.
CAUTION!
Overfilling or underfilling the crankcase will cause
oil aeration or loss of oil pressure. This could damage
your engine.
MAINTAINING YOUR VEHICLE 451
7

Engine Oil Filter
The engine oil filter should be replaced at every engine
oil change.
Engine Oil Filter Selection
The manufacturer's engines have a full-flow type oil
filter. Use a filter of this type for replacement. The quality
of replacement filters varies considerably. Only high-
quality filters should be used to assure most efficient
service. Mopar Engine Oil Filters are a high-quality oil
filter and are recommended.
Drive Belts Ð Check Condition and Tension
Belt tension is controlled by means of an automatic
tensioner. No belt tension adjustments are required.
However, belt and belt tensioner condition should be
inspected at the specified intervals and replaced if re-
quired. See your authorized dealer for service.At the mileage indicated in the maintenance schedule, all
belts and tensioner should be checked for condition.
Improper belt tension can cause belt slippage and failure.
Belts should be inspected for evidence of cuts, cracks,
glazing or frayed cords and replaced if there is indication
of damage which could result in belt failure. Low gen-
erator belt tension can cause battery failure.
Also check belt routing to make sure there is no interfer-
ence between the belts and other engine components.
Spark Plugs (Gas Engines)
Spark plugs must fire properly to assure engine perfor-
mance and emission control. New plugs should be in-
stalled at the specified mileage. The entire set should be
replaced if there is any malfunction due to a faulty spark
plug. Malfunctioning spark plugs can damage the cata-
lytic converter. For proper type of replacement spark
plugs, refer to the ªSpark Plugsº under ªFluids, Lubri-
cants and Genuine Partsº in Section 7.
454 MAINTAINING YOUR VEHICLE

To minimize the possibility of catalyst damage:
²Do not shut off the engine or interrupt the ignition
when the transmission is in gear and the vehicle is in
motion.
²Do not try to start the engine by pushing or towing the
vehicle.
²Do not idle the engine with any spark plug wires
disconnected or removed, such as when diagnostic
testing, or for prolonged periods during very rough
idling or malfunctioning operating conditions.
Emission-Related Components
Positive Crankcase Valve (PCV)
Proper operation of the crankcase ventilation system
requires that the PCV valve be free of sticking or plug-
ging from deposits. Deposits can accumulate in the PCV
valve and passages with increasing mileage. Have the
PCV valve, hoses, and passages checked for proper
operation at the intervals specified. If the valve is
plugged or sticking, replace with a new valveÐdo not
attempt to clean the old PCV valve!Check the ventila-
tion hoses for indications of damage, weepage or plug-
ging with deposits. Replace if necessary.
Maintenance-Free Battery
The top of the maintenance-free battery is permanently
sealed. You will never have to add water, nor is periodic
maintenance required.
MAINTAINING YOUR VEHICLE 457
7

Refrigerant Recovery and Recycling
R-134a Air Conditioning Refrigerant is a hydrofluoro-
carbon (HFC) that is endorsed by the Environmental
Protection Agency (EPA) and is an ozone-saving product.
However, the manufacturer recommends that air condi-
tioning service be performed by authorized dealers or
other service facilities using recovery and recycling
equipment.
Power Steering Ð Fluid Check
Checking the power steering fluid level at a defined
service interval is not required. The fluid should only be
checked if a leak is suspected, abnormal noises are
apparent, and/or the system is not functioning as antici-
pated. Coordinate inspection efforts through an autho-
rized dealer.
WARNING!
Fluid level should be checked on a level surface and
with the engine off to prevent injury from moving
parts and to ensure accurate fluid level reading. Do
not overfill. Use only manufacturers recommended
power steering fluid.
If necessary, add fluid to restore to the proper indicated
level. With a clean cloth, wipe any spilled fluid from all
surfaces. Refer to ªFluids, Lubricants, and Genuine
Partsº in this section for correct fluid type.
Front Suspension Ball Joints
4 x 2 Models
The ball joints and seals should be inspected whenever
the vehicle is serviced for other reasons.
460 MAINTAINING YOUR VEHICLE

Windshield Wiper Blades
The rubber edges of the wiper blades and the windshield
should be cleaned periodically with a sponge or soft cloth
and a mild nonabrasive cleaner. This will remove accu-
mulations of salt or road film.
Operation of the wipers on dry glass for long periods
may cause deterioration of the wiper blades. Always use
washer fluid when using the wipers to remove salt or dirt
from a dry windshield.
Avoid using the wiper blades to remove frost or ice from
the windshield. Keep the blade rubber out of contact with
petroleum products such as engine oil, gasoline, etc.
Windshield Washers
The fluid reservoir is located under the hood and should
be checked for fluid level at regular intervals. Fill thereservoir with windshield washer solvent only (not ra-
diator antifreeze). When refilling the washer fluid reser-
voir, take some washer fluid and apply it to a cloth or
towel and wipe clean the wiper blades, this will help
blade performance.
To prevent freeze-up of your windshield washer system
in cold weather, select a solution or mixture that meets or
exceeds the temperature range of your climate. This
rating information can be found on most washer fluid
containers.
The washer fluid reservoir will hold a full gallon of fluid
when the Low Washer Fluid Light illuminates.
MAINTAINING YOUR VEHICLE 463
7

WARNING!
Exhaust gases can injure or kill. They contain carbon
monoxide (CO) which is colorless and odorless.
Breathing it can make you unconscious and can
eventually poison you. To avoid breathing CO, refer
to Exhaust Gas in the Safety Tips section of this
manual.
Exhaust System Rubber Isolator and Loop-Type
Hanger Ð If Equipped
Inspect surfaces whenever the vehicle is hoisted for
rubber to metal separation or deep cracks. SLIGHT
CRACKING DUE TO WEATHERING DOES NOT AD-
VERSELY AFFECT PERFORMANCE. If, however, exces-
sively deep localized cracks are present, or any part of the
exhaust system abnormally contacts the underbody hard-
ware, the isolator and/or hanger should be replaced.
Cooling System
WARNING!
You or others can be badly burned by hot coolant or
steam from your radiator. If you see or hear steam
coming from under the hood, don't open the hood
until the radiator has had time to cool. Never try to
open a cooling system pressure cap when the radiator
is hot.
Engine Coolant Checks
Check the engine coolant (antifreeze) protection every 12
months (before the onset of freezing weather, where
applicable). If coolant is dirty or rusty in appearance, the
system should be drained, flushed and refilled with fresh
coolant. Check the front of the A/C condenser for any
MAINTAINING YOUR VEHICLE 465
7

accumulation of bugs, leaves, etc. If dirty, clean by gently
spraying water from a garden hose vertically down the
face of the condenser.
Check the coolant recovery bottle tubing for brittle rub-
ber, cracking, tears, cuts and tightness of the connection
at the bottle and radiator. Inspect the entire system for
leaks.
With the engine at normal operating temperature (but
not running), check the cooling system pressure cap for
proper vacuum sealing by draining a small amount of
coolant from the radiator drain cock. If the cap is sealing
properly, the engine coolant (antifreeze) will begin to
drain from the coolant recovery bottle. DO NOT RE-
MOVE THE COOLANT PRESSURE CAP WHEN THE
COOLING SYSTEM IS HOT.Cooling System Ð Drain, Flush and Refill
At the intervals shown on the Maintenance Schedules,
the system should be drained, flushed and refilled.
If the solution is dirty or contains a considerable amount
of sediment, clean and flush with a reliable cooling
system cleaner. Follow with a thorough rinsing to remove
all deposits and chemicals. Properly dispose of old
antifreeze solution.
Selection Of Coolant
Use only the manufacturer's recommended coolant; for
correct coolant type, refer to ªEngine Coolantº under
ªFluids, Lubricants and Genuine Partsº in this section.
466 MAINTAINING YOUR VEHICLE