Set is used to remove and replace the thermostatic fan assembly on Ford 4.9-L E and F series truck engines 1984 through 1993, Ford 4.6-L modular engines, 2.8-L engines 1984 through 1987, 2.9 to 3.0-L Engines, 1988 to current and 4.0-L engines 1990 to current.