Peterbilt 388 Dome Light Bulb Size

The Peterbilt 388 dome light requires a 211-2 bulb size for proper illumination within the interior cabin area of the vehicle. Data for the specific component covers the range from 2011 to 2015.

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
2011-2015	211-2

Bulb Specifications

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

Other Locations

Additional Notes

The Peterbilt 388 uses the 211-2 bulb for its dome light across the 2011-2015 model years.
The 211-2 is an ANSI-standardized bulb, meaning it conforms to a defined specification recognized across the United States and Canada.
The 211-2 is a festoon-type bulb, which is a cylindrical lamp that makes contact at both ends rather than through a screw or bayonet base.
The bulb measures 41mm in length, which is a critical fitment factor, as festoon bulbs must physically span the socket housing to make proper contact.
The 211-2 uses an SV8.5 base, a designation that refers to the end-cap width of the festoon bulb, measured at 8.5mm.
The bulb operates at 12 volts and 12 watts, consistent with standard automotive electrical systems.
Any replacement festoon bulb intended for this application must match the 41mm length and SV8.5 base to ensure proper fitment; a bulb with a different length or base type is not interchangeable.