2008 DODGE RAM 3500 GAS cooling

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

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

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

CAUTION!
²Mixing of coolants other than specified HOAT
engine coolants, may result in engine damage and
may decrease corrosion protection. If a non-HOAT
coolant is introduced into the cooling system in an
emergency, it should be replaced with the speci-
fied coolant as soon as possible.
²Do not use plain water alone or alcohol-base
engine coolant (antifreeze) products. Do not use
additional rust inhibitors or antirust products, as
they may not be compatible with the radiator
engine coolant and may plug the radiator.
²This vehicle has not been designed for use with
Propylene Glycol based coolants. Use of Propy-
lene Glycol based coolants is not recommended.
Adding Coolant
Your vehicle has been built with an improved engine
coolant that allows extended maintenance intervals. This
coolant can be used up to 5 Years or 100,000 miles (160
000 km) before replacement. To prevent reducing this
extended maintenance period, it is important that you
use the same coolant throughout the life of your vehicle.
Please review these recommendations for using Hybrid
Organic Additive Technology (HOAT) coolant. When
adding coolant:
²The manufacturer recommends using Mopart
Antifreeze/Coolant 5 Year/100,000 Mile Formula
HOAT (Hybrid Organic Additive Technology).
²Mix a minimum solution of 50% HOAT engine coolant
and distilled water. Use higher concentrations (not to
exceed 70%) if temperatures below -34ÉF (-37ÉC) are
anticipated.
MAINTAINING YOUR VEHICLE 467
7

²Use only high purity water such as distilled or deion-
ized water when mixing the water/engine coolant
solution. The use of lower quality water will reduce
the amount of corrosion protection in the engine
cooling system.
Please note that it is the owner's responsibility to main-
tain the proper level of protection against freezing ac-
cording to the temperatures occurring in the area where
the vehicle is operated.
NOTE:Mixing coolant types will decrease the life of the
engine coolant and will require more frequent coolant
changes.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of
coolant, and to ensure that coolant will return to the
radiator from the coolant recovery bottle.The cap should be inspected and cleaned if there is any
accumulation of foreign material on the sealing surfaces.
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.
468 MAINTAINING YOUR VEHICLE

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.
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.
Hoses And Vacuum/Vapor Harnesses
Inspect surfaces of hoses and nylon tubing for evidence
of heat and mechanical damage. Hard or soft spots,
brittle rubber, cracking, tears, cuts, abrasions, and exces-
sive swelling indicate deterioration of the rubber.
Pay particular attention to those hoses nearest to high
heat sources such as the exhaust manifold. Inspect hose
routing to be sure hoses do not come in contact with any
heat source or moving component which may cause heat
damage or mechanical wear.
470 MAINTAINING YOUR VEHICLE

EXHAUST SYSTEM
²Removal or rendering inoperative exhaust system
components including the muffler or tailpipe.
ENGINE COOLING SYSTEM
²Removal or rendering inoperative the fan clutch.
²Removal of the fan shroud.
Noise Emission Warranty
The manufacturer warrants that this vehicle as manufac-
tured by the manufacturer, was designed, built and
equipped to conform at the time it left the manufacturer's
control with all applicable U.S. EPA Noise Control Regu-
lations.This warranty covers this vehicle as designed, built and
equipped by the manufacturer, and is not limited to any
particular part, component or system of the vehicle
manufactured by the manufacturer. Defects in design,
assembly or in any part, component or system of the
vehicle as manufactured by the manufacturer, which, at
the time it left the manufacturer's control, caused noise
emissions to exceed Federal standards, are covered by
this warranty for the life of the vehicle.
482 MAINTAINING YOUR VEHICLE