Engine Speed Control; Operating Precautions; Cooling System Tips - Automatic Transmission - Dodge 2009 Ram Diesel Owner's Manual Supplement

50 STARTING AND OPERATING

Engine Speed Control

CAUTION!
Prevent overspeeding the engine going downhill.
When descending steep grades, use a combination of
gears and service brakes to control vehicle/engine
speed. Overspeed can cause severe engine damage.

Operating Precautions

Avoid Overheating The Engine
The temperature of the engine coolant (antifreeze) (a
mixture of 50% ethylene-glycol and 50% water) must not
exceed the normal range of the temperature gauge 240°F
(116°C) with a 16 psi (110 kPa) radiator cap.
Usually the engine coolant (antifreeze) temperature indi-
cated during operation will be to the left of center in the
normal range of the gauge.
Avoid Low Coolant Temperature Operation
Continual operation at low engine coolant (antifreeze)
temperature below the normal range on the gauge 140°F
(60°C) can be harmful to the engine. Low engine coolant
(antifreeze) temperature can cause incomplete combus-
tion which allows carbon and varnish to form on piston
rings and injector nozzles. Also, the unburned fuel can
enter the crankcase, diluting the lubricating oil and
causing rapid wear to the engine.
Cooling System Tips – Automatic Transmission
To reduce potential for engine and transmission over-
heating in high ambient temperature conditions, take the
following actions:
• City Driving —
When stopped, put transmission in NEUTRAL and in-
crease engine idle speed.
• Highway Driving —
Reduce your speed.