Scion xD front and rear turn signal bulbs utilize 7440 and 7440NA sizes respectively, with the front bulb measuring the standard 7440 size and the rear bulb requiring the 7440NA variant. The replacement chart covers 2008 through 2014 model years with corresponding bulb size specifications for each production year.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Scion xD uses the 7440 bulb for the front turn signal across all model years from 2008-2014.
The 7440 is a single-filament wedge bulb in the T20 form factor, rated at 12 volts and 21 watts, and is recognized under the ANSI standard for the US and Canadian markets.
The rear turn signal on the Scion xD uses the 7440NA across all model years from 2008-2014.
The 7440NA shares the same T20 wedge form factor, single-filament construction, and 12V/21W electrical rating as the 7440, with the distinction that its glass envelope is tinted natural amber rather than clear.
Because the 7440NA produces an amber signal through its tinted glass rather than through a colored lens, substituting a clear 7440 in the rear position would alter the color output of the turn signal.
Both the 7440 and 7440NA use a wedge-style base, meaning they are held in place by the socket itself rather than by locking pins or a bayonet mechanism.