GMC P35 / P3500 Dome Light Bulb Size

GMC P35 / P3500 dome light bulb uses a 211-2 size bulb for interior lighting applications. The replacement chart covers vehicle production spanning 1967 to 1968.

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
1967-1968	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 211-2 is the sole bulb type listed for the GMC P35 / P3500 dome light across the 1967-1968 model years.
The 211-2 follows the ANSI standard, making it a regulated specification recognized across the United States and Canada.
As a festoon bulb, the 211-2 is cylindrical in form and mounts by pressing its end caps into spring clips rather than using a threaded or bayonet socket.
The 211-2 has a 41mm length, which is a critical fitment factor, as festoon bulbs must physically span the socket housing to make contact at both ends.
The 211-2 uses an SV8.5 base, a designation that refers to the 8.5mm width of the metal end caps on the festoon body.
The 211-2 operates at 12 volts and 12 watts, consistent with standard 12-volt automotive electrical systems of that era.
Because festoon bulbs are sized by both length and base width, substituting a 211-2 with a festoon of differing length or base size would result in an improper fit even if the voltage and wattage ratings matched.