Ford E-300 front and rear side marker bulbs both utilize a 194 size bulb for optimal operation. The replacement chart covers 1972 to 1974 production years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 194 bulb is the sole bulb type listed across all side marker positions for the Ford E-300 in these specifications.
The 194 is an ANSI-standard miniature wedge bulb, classified under the T10 form factor, and is recognized in both the United States and Canada.
The T10 wedge base design means the bulb is held in place by friction against the socket walls rather than by a bayonet or screw mechanism.
The 194 bulb operates at 12 volts with a power draw of 3.78 watts, placing it in the low-wattage range typical of marker and courtesy lighting applications.
The front side marker position on the Ford E-300 uses the 194 bulb across the 1972-1974 model years.
The rear side marker position carries the same 194 specification for the 1973-1974 model years.
Because the front and rear side marker positions share the same bulb type, a single 194 bulb serves both locations on the vehicle.
The T10 wedge format is a widely produced standard, meaning the 194 bulb is available from numerous manufacturers, though socket fit and voltage tolerance should be confirmed before substitution.