Freightliner 108SD Parking Light Bulb Size

Additional Notes

• The Freightliner 108SD uses the 3457NA bulb for its parking lights across the 2012-2017 model years.
• The 3457NA is an ANSI-standardized bulb type, meaning its physical and electrical specifications conform to a defined North American industry standard recognized in both the United States and Canada.
• This bulb uses a dual-filament design, operating at 27 watts on its high-intensity filament and 7 watts on its low-intensity filament, which allows a single bulb to serve two distinct lighting functions.
• The T25 designation refers to the bulb's tubular glass envelope, with the number indicating its width in eighths of an inch, placing it in a mid-range size category common to automotive signal and parking applications.
• The natural amber glass of the 3457NA produces its amber color through the glass itself rather than through a coating or lens filter, which is a construction distinction relevant to light output consistency over time.
• The bulb operates on a 12-volt electrical system, consistent with standard heavy-duty commercial vehicle electrical architecture.
• The 3457NA shares its base and envelope type with the non-amber 3457 bulb, but the two are not interchangeable in applications where amber output is required by regulation, as the clear version does not replicate the amber tint of the NA variant.