International S1723 front side marker bulbs use 168 or 1895 bulb sizes, while rear side marker bulbs use 168 size. 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 168 bulb is the dominant specification across the International S1723's side marker system, covering both front and rear positions for the 1980-1985 model years, with a single exception in the front side marker position for 1983.
The 168 bulb is an ANSI-standard miniature wedge type with a T10 envelope, rated at 12 volts and 4.9 watts.
The 1895 bulb, specified for the front side marker on the 1983 International S1723, is an ANSI-standard miniature wedge type with a T5 envelope, rated at 12 volts and 0.9 watts.
The T5 envelope of the 1895 bulb is physically smaller than the T10 envelope of the 168 bulb, which means the two types are not interchangeable despite sharing the same wedge base style and operating voltage.
The wattage difference between the 168 (4.9W) and the 1895 (0.9W) is substantial, and substituting one for the other would produce a significant difference in light output at the affected position.
The rear side marker position uses the 168 bulb uniformly across all six model years covered in the specifications, with no variation.