The Kenworth K100E front side marker uses bulb sizes 67, 1157, and 904, while the rear side marker uses sizes 904 and 67. The replacement chart contains vehicle production years and bulb size specifications spanning 1985 to 1997.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Kenworth K100E uses three distinct bulb types across its front and rear side marker positions: the 67, 1157, and 904, all of which conform to ANSI standards recognized in both the United States and Canada.
The 1157 bulb is a dual-filament type with a BAY15d bayonet base, rated at 12V with a wattage split of 21W and 5W across its two filaments. Its dual-filament design distinguishes it from the single-filament bulbs also specified for this vehicle.
The 67 bulb is a single-filament type with a BA15s bayonet base, rated at 12V and 8W. It is considered a lower-wattage variant of the 1156 bulb, and its BA15s base is not interchangeable with the BAY15d base of the 1157 despite a similar physical appearance.
The 904 is a miniature wedge bulb of the T10 type, rated at 12V and 8W. Its wedge base differs fundamentally from the bayonet bases of both the 67 and 1157, making cross-substitution between these types mechanically incompatible.
The front side marker position on the Kenworth K100E uses the 1157 for model years 1985, 1988-1990, and 1993-1996, making it the most frequently specified bulb for that position across the production range covered.
The front side marker position uses the 67 bulb for model years 1986, 1991-1992, and 1997, and the 904 bulb solely for the 1987 model year.
The rear side marker position uses the 904 bulb for model years 1986-1989 and 1992-1997, establishing it as the dominant bulb type for that position.
The rear side marker position uses the 67 bulb for model years 1985, 1990-1991, with no appearance of the 1157 in any rear side marker application across the full range of years listed.
Because the 67 and 1157 both use bayonet-style bases, the difference in base indexing (BA15s versus BAY15d) is a critical fitment consideration. The BAY15d base of the 1157 has offset pins to prevent incorrect installation, and the two types are not interchangeable despite sharing a similar form factor.
The front side marker position shows variation across nearly every few model years, with no single bulb type remaining consistent throughout the entire 1985-1997 span, which reflects the importance of confirming the specific model year before selecting a replacement.