The International 9300 front turn signal bulb operates with a 1156 size, while the rear turn signal bulb uses a 1157 size. The replacement chart covers vehicle production spanning 1988 to 1997.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The International 9300 uses the 1156 bulb for the front turn signal across all listed model years, 1988-1997.
The 1156 is a single-filament bulb operating at 12V and 21W, fitted with a BA15s bayonet base, and recognized under ANSI standards in both the United States and Canada.
The BA15s base designation indicates a single-contact bayonet mount, which is not interchangeable with dual-contact bayonet bases used on other bulb types.
The rear turn signal on the International 9300 uses the 1157 bulb across all listed model years, 1988-1997.
The 1157 is a dual-filament bulb rated at 12V with two wattage outputs, 21W for the turn signal filament and 5W for the secondary filament, and is also an ANSI-recognized standard in the United States and Canada.
The 1157 uses a BAY15d bayonet base, which features two offset pins to ensure correct orientation during installation, distinguishing it from the single-contact BA15s base of the 1156.
Although the 1156 and 1157 share the same 21W primary wattage and 12V operating voltage, their base types differ, making them physically non-interchangeable despite the similarity in output ratings.
The dual-filament design of the 1157 allows the rear turn signal housing to serve more than one lighting function, with the lower-wattage filament typically dedicated to a secondary role such as a running or parking light.