The Buell S3T Thunderbolt front turn signal bulb uses a 5008 size, while rear turn signal applications require either 5008 or 232 bulb sizes. The replacement chart covers vehicle production spanning 1997 to 2002.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 5008 is an ANSI-standard bulb used in both the US and Canadian markets. It operates at 12V and features a BA15s single-contact bayonet base with a single filament, making it a lower-wattage variant of the more common 1156 bulb.
The 232 is also an ANSI-standard bulb for the US and Canadian markets. It is a festoon-type bulb with an SV8.5 base, rated at 12V and 3W.
The Buell S3T Thunderbolt uses the 5008 bulb for the front turn signal across all listed model years: 1997, 1999, 2000, and 2002.
The rear turn signal specification for the S3T Thunderbolt changed between model years. The 1997 and 1999 model years use the 232 festoon bulb, while the 2000 and 2002 model years use the 5008 bayonet bulb.
Because the front and rear turn signals share the same 5008 bulb in the 2000 and 2002 model years, those positions are interchangeable with respect to bulb type in those years.
The 1997 and 1999 model years require two distinct bulb types across the turn signal positions. The front uses the BA15s bayonet-based 5008, while the rear uses the SV8.5 festoon-based 232. These two types are not interchangeable due to their differing base designs.
The BA15s base of the 5008 is a single-contact bayonet fitting, which is physically and electrically incompatible with the SV8.5 festoon base of the 232. Substituting one for the other is not possible without modification to the socket.