check engine DODGE RAM 3500 CHASSIS CAB 2008 3.G Owner's Guide

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, fol-
low the preceding safety tips.
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. If, however,
excessively deep localized cracks are present, or any part
of the exhaust system abnormally contacts the under-
body hardware, 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
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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.
Extremely cold ambient temperature may require the
addition of a ªwinter frontº for effective operation of the
cab heating/cooling system. Make certain that a percent-
age of the radiator is exposed for adequate air flow
through the charge air cooler and automatic transmission
oil cooler. The percentage of opening must be increased
with the increasing ambient air temperature and/or
engine load. If the cooling fan can be heard cycling
frequently, increase the size of the opening in the winter
front.Coolant bottle level check
The coolant reserve system provides a quick visual
method of determining that the coolant level is adequate.
With the engine idling, and warmed to the normal
operating temperature, the level of the coolant on the
coolant bottle should be between the fluid level marks.
Check the coolant level whenever the hood is raised.
The radiator normally remains completely full, so there is
no longer a need to remove the coolant pressure cap
except for checking coolant freeze point or replacement
with new antifreeze coolant.
WARNING!
Never add coolant to the radiator when the engine is
overheated. Do not loosen or remove pressure cap to
cool overheated engine! The coolant is under pres-
sure and severe scalding could result.
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WARNING!
²The warning words ªDO NOT OPEN HOTº on
the cooling system pressure cap are a safety pre-
caution. Never add coolant when the engine is
overheated. Do not loosen or remove the cap to
cool an overheated engine. Heat causes pressure to
build up in the cooling system. To prevent scald-
ing or injury, do not remove the pressure cap while
the system is hot or under pressure.
²Do not use a pressure cap other than the one
specified for your vehicle. Personal injury or en-
gine damage may result.
Disposal Of Used Engine Coolant
Used ethylene glycol based engine coolant is a regulated
substance requiring proper disposal. Check with your
local authorities to determine the disposal rules for yourcommunity. Do not store ethylene glycol-based engine
coolant in open containers or allow it to remain in
puddles on the ground. Prevent ingestion by animals and
children. If ingested by a child, contact a physician
immediately. Clean up any ground spills immediately.
Coolant Level
The coolant bottle provides a quick visual method for
determining that the coolant level is adequate. With the
engine cold, the level of the coolant in the coolant
recovery bottle should be between the ranges indicated
on the bottle.
The radiator normally remains completely full, so there is
no need to remove the radiator cap unless checking for
coolant freeze point or replacing coolant. Advise your
service attendant of this. As long as the engine operating
temperature is satisfactory, the coolant bottle need only
be checked once a month.
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When additional coolant is needed to maintain the
proper level, it should be added to the coolant bottle. Do
not overfill.
Points To Remember
NOTE:When the vehicle is stopped after a few miles (a
few kilometers) of operation, you may observe vapor
coming from the front of the engine compartment. This is
normally a result of moisture from rain, snow, or high
humidity accumulating on the radiator and being vapor-
ized when the thermostat opens, allowing hot coolant to
enter the radiator.
If an examination of your engine compartment shows no
evidence of radiator or hose leaks, the vehicle may be
safely driven. The vapor will soon dissipate.
²Do not overfill the coolant recovery bottle.
²Check coolant freeze point in the radiator and in the
coolant recovery bottle. If antifreeze needs to be
added, contents of coolant recovery bottle must also be
protected against freezing.
²If frequent coolant additions are required, or if the
level in the coolant recovery bottle does not drop when
the engine cools, the cooling system should be pres-
sure tested for leaks.
²Maintain coolant concentration at 50% HOAT engine
coolant (minimum) and distilled water for proper
corrosion protection of your engine which contains
aluminum components.
²Make sure that the radiator and coolant recovery
bottle overflow hoses are not kinked or obstructed.
²Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean, also.
438 MAINTAINING YOUR VEHICLE

²Do not change the thermostat for summer or winter
operation. If replacement is ever necessary, install
ONLY the correct type thermostat. Other designs may
result in unsatisfactory coolant performance, poor gas
mileage, and increased emissions.
Fan
Inspection
Check the fan for cracks and bent or broken blades. If any
of these conditions exist, you must replace the fan. Make
sure it is securely mounted.
NOTE:This service procedure must be performed by a
trained service technician. Make arrangements with your
authorized Dodge Truck Dealer for this inspection.
Charge Air Cooler Ð Inter-Cooler (Diesel
Engines)
The charge air cooler is positioned between the radiator
and the air conditioner condenser. Air enters the engine
through the air cleaner and passes through the turbo-
charger where it is pressurized. This pressurized air
rapidly reaches high temperature. The air is then directed
through a hose to the charge air cooler and through
another hose to the intake manifold of the engine. The air
entering the engine has been cooled by about 50 to 100
degrees Fahrenheit. This cooling process enables more
efficient burning of fuel resulting in fewer emissions.
To guarantee optimum performance of the system, keep
the surfaces of the charge air cooler, condenser and
radiator clean and free of debris. Periodically check the
hoses leading to and from the charge air cooler for cracks
or loose clamps resulting in loss of pressure and reduced
engine performance.
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Brake Master Cylinder ± Brake Fluid Level Check
The fluid level of the master cylinder should be checked
when performing under the hood service, or immedi-
ately if the brake system warning lamp indicates system
failure.
The brake master cylinder has a translucent plastic
reservoir. On the outboard side of the reservoir, there is a
ªMAXº mark and an ªMINº mark (3500 vehicles only)
and a ªFULLº and ªADDº mark (4500/5500 vehicles
only). The fluid level must be kept within these two
marks. Do not add fluid above the full mark because
leakage may occur at the cap.
With disc brakes the fluid level can be expected to fall as
the brake linings wear. However, an unexpected drop in
fluid level may be caused by a leak and a system check
should be conducted.
Refer to Fluids, Lubricants and Genuine Parts for the
correct Fluid type.WARNING!
Use of a brake fluid that may have a lower initial
boiling point, or unidentified as to specification, may
result in sudden brake failure during hard prolonged
braking. You could have an accident.
WARNING!
Overfilling the brake fluid reservoir can result in
spilling brake fluid on hot engine parts and the
brake fluid catching fire.
Use only brake fluid that has been in a tightly closed
container to avoid contamination from foreign matter or
moisture.
442 MAINTAINING YOUR VEHICLE

Automatic Transmission (Gas Engine Only)
Selection Of Lubricant
Refer to Fluids, Lubricants and Genuine Parts for the
correct lubricant type. It is important that the transmis-
sion fluid be maintained at the prescribed level using the
recommended fluid.
CAUTION!
Using a transmission fluid other than the manufac-
turers recommended fluid may cause deterioration in
transmission shift quality and/or torque converter
shudder. Using a transmission fluid other than the
manufacturers recommended fluid will result in
more frequent fluid and filter changes. Refer to
Fluids, Lubricants and Genuine Parts for correct
fluid type.
Fluid Level Check ± 545RFE Transmission
Check the fluid level while the transmission is at normal
operating temperature 180É F (82É C). This occurs after at
least 15 mi (25 km) of driving. At normal operating
temperature the fluid cannot be held comfortably be-
tween the fingertips.
Procedure For Checking Fluid Level
To properly check the automatic transmission fluid level,
the following procedure must be used:
1. Operate the engine at idle speed and normal operating
temperature.
2. The vehicle must be on level ground.
3. Fully apply parking brake.
4. Place the gear selector momentarily in each gear
position ending with the lever in P (Park).
446 MAINTAINING YOUR VEHICLE

Automatic Transmission Fluid and Filter Change
Follow the Maintenance Schedule for recommended
transmission fluid and filter change intervals.
NOTE:If the transmission is disassembled for any
reason, the fluid and filter should be changed.
Special Additives
The manufacturer recommends against the addition of
any additives to the transmission. Exception to this
policy is the use of special dyes to aid in detecting fluid
leaks. The use of transmission sealers should be avoided,
since they may adversely affect seals.
Automatic Transmission (Diesel Engine Only)
Selection Of Lubricant
Refer to Fluids, Lubricants and Genuine Parts for the
correct lubricant type. It is important that the transmis-
sion fluid be maintained at the prescribed level using the
recommended fluid.
CAUTION!
Using a transmission fluid other than the manufac-
turers recommended fluid may cause deterioration in
transmission shift quality and/or torque converter
shudder. Using a transmission fluid other than the
manufacturers recommended fluid will result in se-
rious damage to the transmission. Refer to Fluids,
Lubricants and Genuine Parts for correct fluid type.
Fluid Level Check ± AS68RC Transmission
Check the fluid level while the transmission is at normal
operating temperature 167É F (76É C). This occurs after at
least 15 mi (25 km) of driving. At normal operating
temperature the fluid cannot be held comfortably be-
tween the fingertips.
448 MAINTAINING YOUR VEHICLE

Procedure For Checking Fluid Level
To properly check the automatic transmission fluid level,
the following procedure must be used:
1. The vehicle must be on level ground.
2. Operate the engine at idle speed for a minimum of 60
seconds and normal operating temperature.
3. Fully apply parking brake and press the brake pedal.
4. Place the gear selector momentarily in each gear
position ending with the lever in P (Park). Make sure the
engine is running at idle speed.
5. Remove the dipstick and determine if the fluid is hot
or cold. Hot fluid is approximately 160É F - 175É F (70É C
± 82É C), Which is the normal operating temperature after
the vehicle has been driven at least 15 miles. The fluid can
not be comfortably held between the finger tips. Only usethe cold region on the dipstick as a rough reference when
doing initial oil level set after transmission rebuild or
transmission refill.
6. Wipe the dipstick clean and reinsert it until seated.
7. Remove the dipstick again and note the fluid level on
both sides. The fluid level should be between the HOT
(upper) reference holes on the dipstick at normal operat-
ing temperature. Verify that a solid coating of oil is seen
on both sides of the dipstick. If the fluid is low, add
MopartA68SRCŸ Automatic Transmission Fluid as
required into the dipstick tube.Do not overfill. Never
use any ATF other than MopartAS68RCŸ Automatic
Transmission Fluid.After adding any quantity of oil
through the dipstick tube, wait a minimum of two (2)
minutes for the oil to fully drain into the transmission
before rechecking the fluid level.
NOTE:If it is necessary to check the transmission below
the operating temperature, the fluid level should be
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Air Cleaner Assembly
Inspect air cleaner housing for proper assembly and fit.
Make certain that the air cleaner is properly positioned
and that the cover is tight. Check all hoses leading to the
air cleaner for tightness. The air filter element must also
be clean and serviced according to the instructions out-
lined in the Maintenance Schedule Section of this
manual.
Tampering With Noise Control System Prohibited
Federal law prohibits the following acts or the causing
thereof: (1) the removal or rendering inoperative by any
person, other than for purposes of maintenance, repair, or
replacement, of any device or element of design incorpo-
rated into any new vehicle for the purpose of noise
control prior to its sale or delivery to the ultimate
purchaser or while it is in use, or (2) the use of the vehicle
after such device or element of design has been removed
or rendered inoperative by any person.Among those acts presumed to constitute tampering are
the acts listed below.
²AIR CLEANER
þRemoval of the air cleaner.
þRemoval of the air cleaner filter element from the air
cleaner housing.
þRemoval of the air ducting.
²EXHAUST SYSTEM
þRemoval or rendering inoperative exhaust system
components including the muffler or tailpipe.
²ENGINE COOLING SYSTEM
þRemoval or rendering inoperative the fan clutch.
þRemoval of the fan shroud.
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