Thermostat: Service and Repair

Thermostat - 3.5L, 3.7L













Removal and Installation

1. Drain the cooling system. For additional information, refer to Cooling System Draining, Filling and Bleeding Service and Repair.

2. Remove the Air Cleaner (ACL) assembly and outlet pipe.

3. If a new coolant inlet connection is being installed, release the clamp and disconnect the lower radiator hose from the coolant inlet connection.

4. Remove the 2 bolts and position the coolant inlet connection aside.
- To install, tighten to 10 Nm (89 lb-in).


5. Remove the thermostat and the O-ring seal.
- Clean and inspect the O-ring seal. Install a new seal if necessary.


6. NOTICE: The engine cooling system is filled with Motorcraft(R) Specialty Orange Engine Coolant. Do not mix coolant types. Mixing coolant types degrades the corrosion protection of the coolant.

NOTE: Lubricate the thermostat O-ring seal with clean engine coolant.
To install, reverse the removal procedure.


7. Fill and bleed the cooling system. For additional information, refer to Cooling System Draining, Filling and Bleeding Service and Repair.