Ford L800 front and rear turn signal bulbs utilize 1156 and 1157 sizes. The replacement chart covers 1980 to 1985 production years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Ford L800 turn signal system uses two bulb types across its model years: the 1156 and the 1157, both of which are ANSI-standardized for the US and Canadian markets and operate on a 12-volt electrical system.
The 1156 is a single-filament bulb rated at 21W, fitted with a BA15s bayonet base, which has a single locating pin on its collar.
The 1157 is a dual-filament bulb rated at 21W and 5W, fitted with a BAY15d bayonet base, which has two offset locating pins to prevent incorrect insertion.
Because the BA15s and BAY15d bases are physically distinct, the 1156 and 1157 are not interchangeable without a socket modification, despite sharing the same 12-volt operating voltage.
The Ford L800 front turn signal uses the 1156 for model years 1982-1985 and the 1157 for model years 1980-1981.
The rear turn signal fitment on the Ford L800 is not uniform across its model years, with the 1156 appearing in 1980, 1982, and 1985, while the 1157 is specified for 1981, 1983, and 1984.
Because the rear turn signal alternates between the 1156 and 1157 across individual model years, the specific year of the vehicle must be confirmed before selecting a replacement bulb for that position.
The front and rear turn signals share the same bulb type only in 1982 and 1985, both of which specify the 1156 for each position.
In 1980 and 1981, the front and rear turn signals on the L800 use different bulb types from one another, requiring separate bulb selections for each position on those vehicles.