Some 2021-2022 F-150 vehicles built on or before 08-Mar-2022 and some 2021-2022 Expedition/Navigator vehicles built on or before 14-Mar-2022 equipped with a 3.5L EcoBoost engine may experience a coolant leak at the thermostat housing. This may be due to an incomplete weld on the thermostat housing which can leak during normal vehicle operation. To correct the condition, replace the thermostat housing using service part number ML3Z-8A586-C. Refer to Workshop Manual (WSM), Section 303-03. For claiming, use causal part 8A586 and applicable labor operations in Section 08 of the Service Labor Time Standards (SLTS) Manual.
