Ford Explorer Sport Trac Dome Light Bulb Size

The Ford Explorer Sport Trac dome light uses bulb size 578 or 906 depending on the specific application. Available data for the lighting components covers the range from 2001 to 2010.

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
2007-2010	578
2001-2005	906

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 41mm length, end-cap contacts. 12V, 12W.	578
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 8W.	906

Other Locations

Additional Notes

The Ford Explorer Sport Trac dome light uses two distinct bulb types across its model years, with the 578 fitted in 2007-2010 models and the 906 fitted in 2001-2005 models.
The 578 is a festoon-style bulb measuring 41mm in length with end-cap contacts, meaning it seats by pressing lengthwise between two spring clips rather than inserting into a socket.
The 906 is a T10 miniature wedge bulb, which uses a wedge-shaped base that friction-fits directly into a socket without a separate metal base or pins.
Both bulb types are rated at 12 volts and conform to ANSI standards recognized in both the United States and Canada.
The 578 operates at 12 watts, while the 906 operates at 8 watts, making the 578 a higher-wattage bulb by 4 watts.
The two bulb types are not interchangeable, as they differ in both physical form and wattage, with the festoon and wedge bases requiring entirely different socket designs.
The transition between bulb types occurs between the 2005 and 2007 model years of the Ford Explorer Sport Trac, representing a change in both socket type and wattage for the dome light position.