The Mack LE front and rear side marker bulb size is 1891, a specification applicable to the truck model across multiple production years. The replacement chart covers 1995 to 1997 vehicle production data with corresponding bulb size information.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 1891 bulb is the sole bulb type listed across all side marker positions for the Mack LE, covering model years 1995-1997.
The 1891 is classified as a miniature wedge bulb, designated T5, which refers to its tubular glass envelope with a 5/8-inch width.
The wedge base design means the 1891 requires no separate metal base or locking pins, as the glass envelope itself acts as the retention mechanism within the socket.
The 1891 operates at 12 volts and 2 watts, placing it among the lower-wattage miniature bulbs used in automotive marker lighting applications.
The 1891 carries ANSI standardization recognized in both the United States and Canada, meaning the bulb conforms to a defined set of electrical and physical tolerances.
The same 1891 bulb size is specified for both the front and rear side marker positions on the Mack LE across all listed years, indicating a shared socket type between those two locations.