Harley-Davidson FLHXXX Street Glide Trike Turn Signal Bulb Size

Harley-Davidson FLHXXX Street Glide Trike rear turn signal bulb uses a 3157 size. The replacement chart covers 2010 to 2011 model 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.

Rear Turn Signal

Years	US Type	EU Type	Shop
2010-2011	3157	P27/7W	Check Price

Bulb Specifications

Description	Type	Shop
ANSI standard (US & Canada). Dual-filament wedge bulb (T25). 12V, 27W/7W.	3157	Check Price

Other Locations

Additional Notes

The 3157 bulb is an ANSI-standard dual-filament wedge type, classified under the T25 form factor. It operates at 12 volts and carries two separate wattage ratings: 27W for the high-intensity filament and 7W for the low-intensity filament. This dual-filament design allows a single bulb to serve both turn signal and running light functions simultaneously.
The 3157 designation is recognized under ANSI standards applicable in the United States and Canada, meaning the specification reflects a North American market fitment for the Harley-Davidson FLHXXX Street Glide Trike.
The rear turn signal position on this vehicle used the 3157 bulb across the 2010-2011 model years.
The T25 wedge base of the 3157 bulb is not interchangeable with single-filament bulb types that share a similar physical housing, as the dual-filament construction requires a socket wired to support two independent circuits. Substituting a single-filament bulb in a dual-filament socket results in the loss of one lighting function.