Mitsubishi Fuso FM front and rear side marker bulbs utilize a 89 size across both positions. The replacement chart covers vehicle production spanning 1986 to 1995.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Mitsubishi Fuso FM uses the ANSI 89 bulb for both its front and rear side marker positions across the 1986-1995 model years.
The 89 bulb is an ANSI-standardized type recognized in both the United States and Canada, operating at 12 volts and 13 watts.
It is a single-filament bulb, meaning it serves one lighting function per socket rather than combining two functions such as running light and brake light into a single unit.
The 89 bulb uses a BA15s bayonet base, which is a single-contact bayonet mount with a 15mm collar width, secured by twisting into the socket rather than threading.
The 89 is a lower-wattage variant of the 1156 bulb, which shares the same BA15s bayonet base but draws more power at approximately 26.9 watts.
Because the 89 and 1156 share the same base type, physical fitment into the socket is possible with either bulb, but the wattage difference means they are not electrically interchangeable without consideration of the circuit's design tolerances.
The uniform use of the 89 bulb across both the front and rear side marker positions on the FM simplifies parts sourcing, as a single bulb type covers both locations.