Cooling System
COOLINGDESCRIPTION
5.9L DIESEL
The diesel engine cooling system consists of:
^ Cross-flow radiator
^ Belt driven water pump
^ Cooling fan (attached to the electronic viscous fan drive)
^ Belt driven Electronic viscous fan drive
^ Engine mounted fan shroud
^ Radiator pressure cap
^ Vertically mounted thermostat
^ Coolant reserve/recovery system
^ Engine mounted Transmission oil cooler (Automatic Only)
^ Coolant
Coolant flow circuits for the 5.9L diesel engine are shown in.
OPERATION
COOLING SYSTEM
The cooling system regulates engine operating temperature. It allows the engine to reach normal operating temperature as quickly as possible. It also maintains normal operating temperature and prevents overheating.
The cooling system also provides a source of hot water (coolant) for heating the passenger compartment and cooling the automatic transmission fluid (if equipped). The cooling system is pressurized and uses a centrifugal water pump to circulate coolant throughout the system.
^ When engine is cold the thermostat is closed. The cooling system has no flow through the radiator. The coolant flows through the engine, water pump, and heater.
^ When engine is warm the thermostat is full open. The coolant flows through the radiator, heater, and water pump.
All engines utilize an ambient overflow bottle for coolant recovery/reserve.
An optional factory installed maximum duty cooling package is available on most models. This package will provide additional cooling capacity for vehicles used under extreme conditions such as trailer towing in high ambient temperatures.