Dodge Ram 2500 Dome Light Bulb Size

The Dodge Ram 2500 dome light utilizes bulb sizes 578 and 579 and 211-2 depending on the specific version required for the interior illumination component. Data for the provided specifications covers the range from 1995 through 2010 for the identified vehicle and lighting equipment.

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
2004-2010	578
1998-2003	579
1995-1996	211-2

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 41mm length, end-cap contacts. 12V, 12W.	578
ANSI standard (US & Canada). Festoon bulb, 44mm length, end-cap contacts. 12V, 12W.	579
ANSI standard (US & Canada). Festoon bulb, 41mm length, SV8.5 base. 12V, 12W.	211-2

Other Locations

Additional Notes

The Dodge Ram 2500 dome light uses three distinct bulb sizes across its model years: the 578, 579, and 211-2.
All three bulb types share the same voltage and wattage rating of 12V and 12W, and all three conform to ANSI standards applicable in both the United States and Canada.
Each of the three bulb types is a festoon-style bulb, meaning it is cylindrical in shape and mounts by pressing its two end contacts against spring-loaded holders within the fixture.
The 578 and 211-2 bulbs share a 41mm length, while the 579 is slightly longer at 44mm, making the 579 physically incompatible as a direct substitute for the other two despite identical voltage and wattage ratings.
Although the 578 and 211-2 are both 41mm festoon bulbs with matching electrical ratings, they use different base types. The 578 uses plain end-cap contacts, while the 211-2 uses an SV8.5 base, which affects socket compatibility.
The Dodge Ram 2500 (1998-2010) uses either the 578 or 579 for its dome light, with the 578 specified for 2004-2010 and the 579 specified for 1998-2003.
The 1995-1996 model years specify the 211-2 bulb, which is the only festoon type among the three that carries a named base designation rather than relying solely on end-cap contact fitment.
The shift from the 211-2 to the 579 between the 1996 and 1998 model years represents a change in both base type and physical length for the dome light socket.
The transition from the 579 to the 578 between the 2003 and 2004 model years involves a 3mm reduction in bulb length while retaining the same end-cap contact style and identical electrical characteristics.