Ford L8000F Headlight Bulb Size

Additional Notes

• The Ford L8000F accommodates three distinct headlamp configurations across its 1987-1997 model range: a two-round-lamp setup, a four-rectangular-lamp setup, and a composite headlamp setup. Each configuration requires a different bulb type for both high and low beam positions, and the correct bulb is determined strictly by which headlamp configuration is installed on the vehicle.
• The H6024 is a 7-inch round sealed beam unit operating at 12V and conforming to ANSI standards for the US and Canadian markets. As a sealed beam, the entire unit is replaced rather than an individual bulb. It serves as both the high beam and low beam bulb in the two-round-lamp configuration across all 1987-1997 model years covered by these specifications.
• The H4651 and H4656 are both 4x6-inch rectangular sealed beam units rated at 12V under the same ANSI standard. Like the H6024, neither accepts a replaceable internal bulb; the whole unit is exchanged upon failure. In the four-rectangular-lamp configuration, the H4651 handles the high beam position and the H4656 handles the low beam position, a distinction that applies across all 1987-1997 model years in these specifications.
• The 9007 is a dual-filament halogen bulb with a PX29t base, rated at 12V with a high beam output of 65W and a low beam output of 55W. It handles both beam functions within a single bulb in the composite headlamp configuration and appears in the specifications for 1992-1997 model years.
• The 9004 is a dual-filament halogen bulb with a P29t base, rated at 12V with a high beam output of 65W and a low beam output of 45W. It was used in the composite headlamp configuration for the 1990-1991 model years. The 9004 and 9007 share a similar dual-filament design but differ in base type and low beam wattage, making them non-interchangeable despite their functional similarity.
• The composite headlamp configuration was not present in the 1987-1989 model years according to these specifications, as those years list only the two-round-lamp and four-rectangular-lamp options. The composite option with the 9004 bulb first appears in 1990.
• All five bulb types listed in these specifications conform to ANSI standards applicable in both the United States and Canada, indicating that the same bulb designations are valid across both markets without regional substitution.
• Because the H4651 and H4656 are separate sealed beam units designated for different beam positions in the same four-lamp housing, substituting one for the other would result in incorrect beam function. The physical similarity of the two units makes position-specific installation a critical fitment consideration.