MG TF front turn signal bulb uses 1176 size while rear turn signal bulb uses 1003 size. The replacement chart covers 1954 to 1955 production years with corresponding bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The MG TF uses two distinct bulb types across its turn signal positions: the 1176 for the front and the 1003 for the rear, across both the 1954-1955 model years.
The 1176 is an ANSI-standardized bulb recognized in the US and Canada, operating on a 12-volt system and carrying a dual-filament design intended for specialty applications.
A dual-filament bulb such as the 1176 contains two separate filaments within a single envelope, allowing it to serve more than one lighting function depending on how the socket circuit is wired.
The 1003 is also an ANSI-standardized bulb recognized in the US and Canada, rated at 12 volts and 21 watts, and fitted with a BA15s bayonet base.
The BA15s designation on the 1003 refers to a single-contact bayonet base with a 15mm collar, which is a common base type in automotive rear lighting applications.
The 1003 is a single-filament bulb, meaning it performs only one lighting function per socket, consistent with a dedicated rear turn signal role.
The front and rear turn signal positions on the MG TF require different bulb types and are not interchangeable, as the 1176 and 1003 differ in filament count, wattage rating, and base configuration.