DODGE RAM 3500 DIESEL 2008 3.G Owners Manual

Circulation
The cab is designed with features to promote outside air
circulation. There are grilles in the cab back panel. These
are air exhausters that provide the means for regular
exchange of cab air.
Side window demisters direct airflow specifically to the
window glass to help prevent interior fogging of the
glass. They are located in the extreme outside upper
edges of the instrument panel. The demisters also pro-
vide extra air ducts for circulation. They are in operation
whenever the Floor, Mix or Defrost modes are in use.
NOTE:When you turn off the engine you may hear a
hissing sound from under the hood for a short period of
time. This is a normal condition that occurs if the air
conditioning system has been on. It is not an indication of
a problem with the air conditioning system.
Rear Air Duct (Mega Cab Only) Ð If Equipped
The rear seat will receive airflow in all modes except for
Defrost.
The rear air duct is designed to be pointed up when in
A/C mode, and pointed down in Heat mode.
Mega Cab Rear Air Duct
UNDERSTANDING YOUR INSTRUMENT PANEL 259
4

Operating Tips
Fast Cooldown
For a fast cooldown, turn the blower fan rotary knob to
the extreme right position, turn the mode control to the
panel fresh position, press the snowflake button to turn
on the air conditioning, and drive with the windows
open for the first few minutes. Once the hot air has been
expelled, close the windows and press the recirculation
pushbutton, on dual-zone control, or switch the mode
from panel/fresh to panel/recirculate on single-zone
control. When a comfortable condition has been reached,
choose a mode position and adjust the temperature
control slide and blower speed as necessary to maintain
comfort. For high humidity conditions it may be neces-
sary to remain in the Recirculation mode to maintain
comfort.
Window Fogging
Windows will fog on the inside when the humidity inside
the vehicle is high. This often occurs in mild or cool
temperatures when it's rainy or humid. In most cases
turning on the air conditioning (pressing the snowflake
button) will clear the fog. Adjust the temperature control,
air direction and blower speed to maintain comfort.
As the temperature gets colder it may be necessary to
direct air onto the windshield by using MIX Mode
position on the control. Adjust the temperature control
and blower speed to maintain comfort. Higher blower
speeds will reduce fogging. Interior fogging on the
windshield can be quickly removed by selecting the
defrost mode.
Regular cleaning of the inside of the windows with a
non-filming cleaning solution (vinegar and water works
very well) will help prevent contaminates (cigarette
smoke, perfumes, etc.) from sticking to the windows.
Contaminates increase the rate of window fogging.
260 UNDERSTANDING YOUR INSTRUMENT PANEL

Summer Operation
Air conditioned vehicles must be protected with a high
quality antifreeze coolant during summer to provide
proper corrosion protection and to raise the boiling point
of the coolant for protection against overheating. A 50 %
concentration is recommended. For proper coolant type,
refer to ªRecommended Fluids and Genuine Partsº in
Section 7.
When using the air conditioner in extremely heavy traffic
in hot weather, especially when towing a trailer, addi-
tional engine cooling may be required. If this situation is
encountered, operate the transmission in a lower gear to
increase engine RPM, coolant flow and fan speed. When
stopped in heavy traffic, it may be necessary to shift into
NEUTRAL and depress the accelerator slightly for fast
idle operation to increase coolant flow and fan speed.NOTE:On models equipped with Diesel engines, the
idle speed will automatically increase to 1000 rpm at
elevated coolant temperatures to improve engine cooling.
Your air conditioning system is also equipped with an
automatic recirculation system. When the system senses
a heavy load or high heat conditions, it may use partial
Recirculation A/C mode to provide additional comfort.
Winter Operation
When operating the system during the Winter months,
make sure the air intake, located directly in front of the
windshield, is free of ice, slush, snow, or other obstruc-
tions.
UNDERSTANDING YOUR INSTRUMENT PANEL 261
4

Operating Tips Chart
262 UNDERSTANDING YOUR INSTRUMENT PANEL

STARTING AND OPERATING
CONTENTS
mStarting Procedures ± Diesel Engines.........268
NAutomatic Transmission ± If Equipped......268
NManual Transmission ± If Equipped........269
NNormal Starting Procedure ± Engine Manifold
Air Temperature Above 66ÉF (19ÉC)........269
NStarting Procedure ± Engine Manifold Air
Temperature Below 66ÉF (19ÉC)...........270
NStarting Fluids.......................274
mNormal Operation (Diesel Engine)...........274
NCold Weather Precautions...............275NEngine Idling........................278
NStopping The Engine...................280
NEngine Speed Control..................281
NOperating Precautions..................281
NCooling System Tips Ð Automatic
Transmission........................281
mDiesel Exhaust Brake (Engine Braking) ±
If Equipped...........................283
mTransmission Shifting....................285
NAutomatic Transmission With Overdrive
(68RFE) Ð If Equipped.................285
5

mManual Transmission....................291
NShifting............................291
NDownshifting........................293
NReverse Shifting......................294
mFour±Wheel Drive Operation Ð If Equipped . . . 294
NManually Shifted Transfer Case Operating
Information/Precautions................294
NShifting Procedure - Manually Shifted Transfer
Case..............................297
NTransfer Case Reminder Light............298
NElectronically Shifted Transfer Case Operating
Information/Precautions (4 Position Switch) Ð
If Equipped.........................299
NShifting Procedure Ð Electronically Shifted
Transfer Case........................303mLimited-Slip Differential Ð If Equipped.......306
mDriving On Slippery Surfaces..............307
mDriving Through Water..................307
NFlowing/Rising Water..................307
NShallow Standing Water.................308
mDriving Off-Road.......................309
mParking Brake.........................310
mBrake System..........................312
NBrake Noise.........................312
NFour-Wheel Anti-Lock Brake System........313
mPower Steering........................315
mTire Safety Information...................316
NTire Markings........................316
264 STARTING AND OPERATING

NTire Identification Number (TIN)..........319
NTire Loading And Tire Pressure...........320
mTires Ð General Information...............324
NTire Pressure.........................324
NTire Inflation Pressures.................325
NRadial Ply Tires......................327
NCompact Spare Tire Ð If Equipped.........328
NLimited-Use Spare Ð If Equipped.........328
NTire Spinning........................329
NTread Wear Indicators..................330
NLife Of Tire.........................330
NReplacement Tires.....................331
NAlignment And Balance.................332mSupplemental Tire Pressure Information Ð If
Equipped............................333
mTire Chains...........................333
mSnow Tires...........................335
mTire Rotation Recommendations............335
NDual Rear Wheels.....................337
mTire Pressure Monitor System (TPMS) Ð
If Equipped...........................338
NTire Pressure Monitor System (TPMS) ªLight
Loadº Reset Switch Description ±
If Equipped.........................341
NTire Pressure Monitor System Components . . . 344
NGeneral Information...................347
mEngine Runaway.......................347
STARTING AND OPERATING 265
5

mFuel Requirements......................348
NFuel Requirements (6.7L Diesel Engines).....348
mAdding Fuel (Diesel Engines)..............349
NFuel Filler Cap (Gas Cap)...............350
NBulk Fuel Storage.....................351
mVehicle Loading........................352
NCertification Label.....................352
mTrailer Towing.........................356
NCommon Towing Definitions.............356
NTrailer Hitch Classification...............360
NTrailer Towing Weights (Maximum Trailer
Weight Ratings)......................361NTrailer And Tongue Weight..............361
NTowing Requirements..................362
NTowing Tips.........................368
NTrailer Towing Mirrors Ð If Equipped......370
mSnowplow............................371
NBefore Plowing.......................372
NSnowplow Prep Package Model Availability . . 372
NOver The Road Operation With Snowplow
Attached...........................373
NMethods For Removing Snow............373
NOperating Tips.......................373
NGeneral Maintenance...................374
266 STARTING AND OPERATING

mRecreational Towing (Behind Motorhome, Etc.) . . 375
NRecreational Towing ± 2-Wheel Drive
Models............................375NRecreational Towing ± 4-Wheel Drive
Models............................375
STARTING AND OPERATING 267
5

STARTING PROCEDURES ± DIESEL ENGINES
Before starting your vehicle, adjust your seat, adjust both
inside and outside mirrors, and fasten your seat belts.
The starter should not be operated for more than 15-
second intervals. Waiting a few minutes between such
intervals will protect the starter from overheating.
WARNING!
Be sure to turn off the engine and remove the key
from the ignition switch if you want to rest or sleep
in your vehicle. Accidents can be caused by inadvert-
ently moving the shift lever or by pressing the
accelerator pedal. This may cause excessive heat in
the exhaust system, resulting in overheating and
vehicle fire which may cause serious or fatal injuries.
WARNING!
Do not leave children or animals inside parked
vehicles in hot weather. Interior heat build up may
cause serious injury or death.
Automatic Transmission ± If Equipped
Start the engine with the shift lever in NEUTRAL or
PARK position. Apply the brake before shifting to any
driving range.
The CumminstDiesel engine is equipped with several
features designed to assist cold weather starting and
operation:
²The engine block heater is a resistance heater installed
in the water jacket of the engine just above and behind
the oil filter. It requires a 110±115 volt AC electrical
outlet with a grounded, three-wire extension cord.
268 STARTING AND OPERATING