Peterbilt 382 front turn signal bulbs use 3157NA size while rear turn signal bulbs use 1157 size. Replacement chart data covers 2011 to 2017 vehicle production years with corresponding bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Peterbilt 382 front turn signal position uses the 3157NA bulb across all 2011-2017 model years covered in these specifications.
The 3157NA is a dual-filament T25 wedge bulb rated at 12V with a 27W high filament and a 7W low filament, constructed with natural amber glass rather than a clear envelope.
The natural amber glass of the 3157NA produces its amber color through the glass itself, which distinguishes it from standard clear 3157 bulbs that rely on a colored lens housing to achieve the same effect.
The rear turn signal position on the Peterbilt 382 uses the 1157 bulb across all 2011-2017 model years covered in these specifications.
The 1157 is a dual-filament bulb rated at 12V with a 21W high filament and a 5W low filament, mounted on a BAY15d bayonet base.
The BAY15d bayonet base of the 1157 and the wedge base of the 3157NA are physically incompatible with each other, meaning the front and rear turn signal sockets on the Peterbilt 382 do not accept the same bulb.
Both the 3157NA and the 1157 conform to ANSI standards applicable in the United States and Canada, placing them within a standardized classification system for automotive lighting components.
The dual-filament design of both bulbs allows a single unit to serve two lighting functions, typically a brighter filament for the active turn signal flash and a dimmer filament for a running light or parking light role.