Cooling System: Description and Operation

Engine Cooling

NOTICE: Always fill the cooling system with the manufacturer's specified coolant. If a non-specified coolant has been used the cooling system must be chemically flushed. Refer to Cooling System Flushing . Failure to follow these instructions may damage the engine or cooling system.

The cooling system components include the following:

- Block heater (mounted in the LH side at the rear of the engine block for 6.2L engines and the RH side at the rear of the engine block for 6.8L engines)

- Cooling fan blade

- Electric cooling fan clutch- 6.2L engines

- Mechanical cooling fan clutch- 6.8L engines

- Cooling fan shroud

- Radiator

- Degas bottle

- Pressure relief cap

- Radiator draincock

- Coolant pump

- Coolant thermostat

- Oil filter adapter

- Upper radiator hose

- Lower radiator hose

- Degas bottle supply hose

- Heater core

- Heater hoses

Engine coolant provides freeze protection, boil protection, cooling efficiency and corrosion protection to the engine and cooling components. In order to obtain these protections, the engine coolant must be maintained at the correct concentration and fluid level in the degas bottle.

When adding engine coolant, use a 50/50 mixture of engine coolant and distilled water. A coolant concentration of 50% will provide freeze point protection down to -37°C (-34°F).

To maintain the integrity of the coolant and the cooling system:

- NOTICE: With the engine cold, fill vehicles to within the cold fill range shown on the degas bottle. This fill level will allow for coolant expansion. Overfilling the degas bottle may result in damage to the pressure cap, which can cause the engine to overheat.

Add Motorcraft(R) Specialty Orange Engine Coolant or equivalent. Do not mix coolant types.

- Do not add/mix any other engine coolant. Mixing coolants may degrade the coolant's corrosion protection.

- Do not add alcohol, methanol, brine or any engine coolants mixed with alcohol or methanol antifreeze. These can cause engine damage from overheating or freezing.

- Do not mix with recycled coolant. Use of such coolants may harm the engine and cooling system components. Do not mix coolant types.

Coolant Flow Diagram, 6.2L

NOTE: Black arrows indicate hot, white arrows indicate cold.










Coolant Flow Diagram, 6.8L

NOTE: Black arrows indicate hot, white arrows indicate cold.