Dodge 2004 Ram Pickup 3500 - Manual (Page 214)

Arctic Operation
Where there are no provisions to keep the engine warm
when it is operating in ambient temperatures consistently
below (-10°F/-23°C), use 5W-40 synthetic engine oil and
fuel that meets the requirements in Section 7, “Mainte-
nance Procedures,” Engine Oil Selection.
Engine Warm-Up
Avoid full throttle operation when the engine is cold.
When starting a cold engine, bring the engine up to
operating speed slowly to allow the oil pressure to
stabilize as the engine warms up.
NOTE: High-speed, no-load running of a cold engine
can result in excessive white smoke and poor engine
performance. No-load engine speeds should be kept
under 1,200 rpm during the warm-up period, especially
in cold ambient temperature conditions.
If temperatures are below 32°F (0°C), operate the engine
at moderate speeds for 5 minutes before full loads are
applied.
Engine Idling — In Cold Weather
Avoid prolonged idling. Long periods of idling may be
harmful to your engine because combustion chamber
temperatures can drop so low that the fuel may not burn
completely. Incomplete combustion allows carbon and
varnish to form on piston rings and injector nozzles.
Also, the unburned fuel can enter the crankcase, diluting
the oil and causing rapid wear to the engine.
NOTE:
• If ambient temperatures are low and the coolant
temperature is below 200°F (93°C), the engine idle
speed will slowly increase to 1000 RPM after 2 minutes
of idle, if the following conditions are met:
• foot is off brake pedal and throttle pedal
214 STARTING AND OPERATING