2008 DODGE RAM 5500 CHASSIS CAB coolant temperature

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.
434 MAINTAINING YOUR VEHICLE

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 before
replacement. To prevent reducing this extended mainte-
nance period, it is important that you use the same
coolant throughout the life of your vehicle. Please review
these recommendations for using Hybrid Organic Addi-
tive Technology (HOAT) coolant.
When adding coolant, a minimum solution of 50% rec-
ommended Mopar Antifreeze/ Coolant 5 Year/100,000
Mile Formula HOAT (Hybrid Organic Additive Technol-
ogy), or equivalent, in water should be used. Use higher
concentrations (not to exceed 70%) if temperatures below
234ÉF (237ÉC ) are anticipated.
Use only high purity water such as distilled or deionized
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 insure 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.
436 MAINTAINING YOUR VEHICLE

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.
MAINTAINING YOUR VEHICLE 437
7

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.
MAINTAINING YOUR VEHICLE 439
7

Radiator Cap......................... 436
Selection of Coolant (Antifreeze).........435,476
Temperature Gauge..................... 176
Cruise Control (Speed Control).............. 132
Cup Holder............................ 154
Customer Assistance..................... 500
Data Recorder, Event...................... 57
Daytime Running Lights................... 125
Dealer Service.......................... 403
Defroster, Rear Window.................85,161
Defroster, Windshield................75,235,238
Delay (Intermittent) Wipers................. 128
Diesel Exhaust Brake..................... 270
Diesel Fuel............................ 341
Diesel Fuel Requirements.................. 341
Bulk Storage of........................ 346
Differential, Limited-Slip.................. 301
Dipsticks.............................. 406Power Steering........................ 428
Disc Brakes............................ 440
Disposal.............................. 412
Engine Oil........................... 412
Used Coolant (Antifreeze)................ 437
Door Locks............................. 27
Door Locks, Automatic.................... 146
Downshifting.......................... 288
Draining Fuel/Water Separator Filter.......... 417
Drive Belts............................ 413
Driving
Through Flowing, Rising, or Shallow Standing
Water.............................. 305
Dual Rear Wheels.....................336,386
DVD Player (Video Entertainment System)...... 226
Electric Rear Window Defrost.............85,161
Electrical Power Outlets................... 151
Electronic Speed Control (Cruise Control)...... 132
INDEX 513
10

Electronic Vehicle Information Center (EVIC).... 143
Electronically Shifted Transfer Case........... 294
Emergency Brake........................ 308
Emergency, In Case of
Freeing Vehicle When Stuck............... 393
Hazard Warning Flasher................. 378
Jacking............................. 380
Jump Starting......................... 390
Tow Hooks.......................... 394
Towing............................. 395
Emission Control System Maintenance......... 480
Emission Related Components.............. 425
Engine............................400,401
Air Cleaner........................413,414
Block Heater....................256,264,270
Break-In Recommendations................ 71
Compartment......................... 400
Compartment Identification............... 401
Coolant (Antifreeze).................... 476Cooling............................. 433
Data Plate........................... 403
Exhaust Gas Caution.................... 340
Flooded, Starting...................... 253
Identification......................... 400
Idling.............................. 266
Jump Starting......................... 390
Oil ..............................406,476
Oil Filler Cap......................408,410
Oil Selection.......................... 408
Oil Synthetic.......................265,410
Runaway............................ 337
Temperature Gauge..................... 176
Event Data Recorder...................... 57
Exhaust Brake.......................... 270
Exhaust Gas Caution................74,340,433
Exhaust System.................74,432,433,452
Exterior Lighting........................ 124
514 INDEX

Gas Cap (Fuel Filler Cap)...............344,402
Gasoline (Fuel)......................... 337
Gasoline, Reformulated................... 338
Gauges............................... 174
Coolant Temperature.................... 176
Fuel................................ 183
Oil Pressure.......................... 176
Speedometer......................... 175
Tachometer.......................... 175
Voltmeter.........................174,262
Gear Ranges......................274,279,287
General Information....................18,113
Glass Cleaning.......................... 461
Grocery Bag Retainer..................... 161
Gross Axle Weight Rating.................. 352
Gross Vehicle Weight Rating................ 351
Guide, Body Builders...................... 7
GVWR............................... 348Hands-Free Phone (UConnectŸ).............. 87
Hazard
Driving Through Flowing, Rising, or Shallow
Standing Water........................ 305
Hazard Warning Flasher................... 378
Head Restraints......................... 116
Headlights............................ 468
Cleaning............................ 460
High Beam........................... 127
High Beam/Low Beam Select Switch........ 127
Lights On Reminder.................... 125
Passing............................. 127
Switch.............................. 124
Heated Mirrors.......................85,161
Heated Seats........................... 119
Heater............................... 237
Heater, Engine Block..................... 270
High Beam/Low Beam Select (Dimmer) Switch . . 127
516 INDEX