Freightliner Argosy Parking Light Bulb Size

The Freightliner Argosy parking light requires bulb size 5702AK or 4157NA depending on the specific application. Data for the bulb sizes covers the range from 2005 to 2007.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
2007	5702AK
2005-2006	4157NA

Bulb Specifications

Description	Bulb Size
Sylvania part number for a coated variant of the ANSI 3157 bulb. Dual-filament wedge bulb (T25), amber coating. 12V, 27W/7W.	5702AK
ANSI standard (US & Canada). Dual-filament wedge bulb (T25), natural amber glass. 12V, 27W/7W.	4157NA

Other Locations

Additional Notes

The Freightliner Argosy uses two distinct bulb part numbers across its 2005-2007 model years for the parking light position: 4157NA for 2005-2006 and 5702AK for 2007.
Both bulbs share the same T25 wedge base form factor and identical electrical ratings of 12V with a dual-filament output of 27W on the high filament and 7W on the low filament, making them functionally equivalent in power draw and socket fitment.
The 4157NA is an ANSI-standardized part recognized across the US and Canadian markets, with amber color produced through natural amber-tinted glass rather than a coating applied to the bulb envelope.
The 5702AK is a Sylvania-specific part number referencing a coated variant of the ANSI 3157 bulb, where the amber output is achieved through a surface coating rather than tinted glass.
Because the amber effect is produced by different methods, the two bulbs are not visually identical despite sharing the same base type, wattage, and voltage rating. Substituting one for the other may produce a slight difference in the color tone of the emitted light.
The dual-filament design in both bulbs serves two independent circuits within a single housing, a configuration typical of parking light positions that also function as turn signals or running lights.