The Volvo VN front turn signal bulb measures 3357 in size, while the rear turn signal bulb measures 1157 in size. A replacement chart covering 1998 to 2004 model years contains vehicle production specifications and corresponding bulb sizes.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Volvo VN uses the 3357 bulb for the front turn signal across the 1998-1999 and 2004 model years.
The 3357 is an ANSI-standard single-filament wedge bulb in a T25 form factor, rated at 12V and 27W.
A single-filament design means the 3357 serves one lighting function only, which in this application is the turn signal.
The rear turn signal on the Volvo VN uses the 1157 bulb across the same model years covered in the specifications.
The 1157 is an ANSI-standard dual-filament bulb with a BAY15d bayonet base, rated at 12V with a 21W/5W output split between its two filaments.
The dual-filament configuration of the 1157 allows it to serve two separate lighting functions within a single housing, with the higher wattage filament typically handling the turn signal and the lower wattage filament handling a secondary function such as a running light.
The BAY15d bayonet base of the 1157 features two offset pins, which prevents incorrect insertion and distinguishes it from single-filament bayonet bulbs that use a BAY15s base with aligned pins.
Both the 3357 and 1157 conform to ANSI standards applicable in the United States and Canada, indicating they meet a defined set of performance and dimensional criteria for those markets.
The 3357 and 1157 are not interchangeable with each other, as they differ in base type, filament count, and wattage rating.