Dodge Ram 2500 front and rear side marker bulbs utilize 3157, 3157NA, 12961, and 194 bulb sizes depending on location and model variation. The replacement chart covers 1994 through 2010 production 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.
The 3157NA is the most frequently specified front side marker bulb across the Dodge Ram 2500, covering model years 1994-2002 and 2009. It is a dual-filament T25 wedge bulb rated at 12V with a 27W high filament and 7W low filament, distinguished from the standard 3157 by its natural amber-tinted glass envelope.
The natural amber glass of the 3157NA produces an amber light output without the use of an amber-tinted lens, which is why it is specified separately from the clear 3157 despite sharing identical electrical ratings and a T25 wedge form factor.
The 3157 and 3157NA are electrically and physically interchangeable, as both are T25 dual-filament wedge bulbs operating at 12V, 27W/7W under the same ANSI standard. The distinction is purely the glass color, which affects whether the housing lens or the bulb itself provides the amber output.
The 3057 is specified for the Dodge Ram 2500 front side marker in 2004-2005. It shares the T25 wedge form factor and 12V, 27W/7W dual-filament rating with the 3157 family, though the 3057 and 3157 differ in their filament orientation and are not universally interchangeable across all applications.
The 12961 is a Philips-designated miniature T10 wedge bulb with a W2.1x9.5d base, rated at 12V and 5W. It is specified for the Dodge Ram 2500 front side marker in 2006-2008, representing a significantly lower wattage than the dual-filament T25 bulbs used in surrounding model years.
The 194 is specified for the rear side marker across model years 1994-2002. It is a single-filament miniature T10 wedge bulb rated at 12V and 3.78W, making it the lowest-wattage bulb in these specifications and a common low-intensity marker application.
For the 2010 Dodge Ram 2500 front side marker, the required bulb type depends on the headlamp configuration. The two-headlamp variant uses the standard clear 3157, while the four-headlamp variant uses the 3157NA with natural amber glass.
The rear side marker transitions from the 194 miniature wedge bulb used through 2002 to the higher-wattage 3157 dual-filament T25 wedge bulb in 2004 and 2006-2007. These two bulb types are not interchangeable due to differences in wattage, filament count, and physical size.
The 3157 specified for the rear side marker in 2004 and 2006-2007 is a clear-glass bulb, unlike the 3157NA used in the front positions. In a rear marker context, the housing lens typically provides any required red coloring rather than the bulb itself.
The 12961 bulb, specified for the front side marker in 2006-2008, carries a manufacturer part number rather than an ANSI designation, which means direct substitution requires confirming that a replacement matches the W2.1x9.5d base type and the 12V, 5W rating.