Peterbilt 379 Dome Light Bulb Size

The Peterbilt 379 dome light utilizes a specific bulb size identified as 97 for the interior lighting component. Data for the specified vehicle covers a range from 1986 to 1997.

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
1986-1997	97 (With 2 Rectangular Headlamps)

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Variant of 1156. 12V, 13W.	97

Other Locations

Additional Notes

The Peterbilt 379 uses the size 97 bulb for the dome light across the 1986-1997 model years, exclusively in configurations with 2 rectangular headlamps.
The 97 bulb is an ANSI-standardized type recognized in both the United States and Canada, operating at 12 volts and 13 watts.
A BA15s bayonet base defines the 97 bulb's mounting interface, meaning it seats with a single pin and a twist-lock motion rather than a screw thread.
The 97 is a single-filament bulb, which means it produces one fixed level of output with no high or low mode.
The 97 bulb is a variant of the 1156, a widely used automotive bulb type, though the two are not necessarily interchangeable due to differences in wattage and base pin positioning tolerances.
The headlamp configuration noted in the specifications, specifically 2 rectangular headlamps, is a fitment condition tied to the dome light bulb size, indicating that trucks with different headlamp arrangements may require a different bulb.