Kenworth W900 front and rear side marker bulbs utilize 67, 904, and 1157 bulb sizes across different applications. The replacement chart covers 1981 through 1997 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 Kenworth W900 front and rear side marker positions draw from three distinct bulb types across the 1981-1997 model years: the 67, 904, and 1157, all of which conform to ANSI standards recognized in both the United States and Canada.
The 904 is a miniature wedge-style T10 bulb rated at 12V and 8W, and it is the most frequently specified bulb across both the front and rear side marker positions on the W900 throughout this period.
The 1157 is a dual-filament bulb with a BAY15d bayonet base, rated at 12V with a 21W main filament and a 5W secondary filament. Its dual-filament construction distinguishes it functionally from the other two bulb types listed in these specifications.
The 67 uses a BA15s single-contact bayonet base and is rated at 12V and 8W. Although it shares a wattage rating with the 904, its bayonet base mount makes it physically incompatible with wedge-style sockets.
The 1157 and the 67 both use bayonet-style bases, but their base types differ. The 1157 uses a BAY15d indexing base with two offset pins, while the 67 uses a BA15s base with a single contact, making the two bulbs non-interchangeable despite any superficial similarity in form.
The front side marker on the W900 uses the 1157 for model years 1982-1985, 1990-1991, and 1994-1995, meaning a dual-filament bulb was specified for that position across those years.
The rear side marker position specified the 1157 only for the 1981 and 1983 model years, with all other rear side marker entries in these specifications calling for either the 904 or the 67.
The 904 and the 67 share the same voltage and wattage ratings of 12V and 8W, but their socket types are incompatible. The 904 seats into a wedge-style socket, while the 67 requires a BA15s bayonet socket, so the two are not interchangeable despite identical electrical ratings.
For the 1997 model year, the front side marker uses the 67 while the rear side marker uses the 904, indicating that the two positions on the same vehicle year do not necessarily share the same bulb type.
The front side marker for the 1996 model year specifies the 904, whereas the rear side marker for that same year specifies the 67, again reflecting that front and rear marker positions on the W900 can require different bulb types within a single model year.