GMC P152 front and rear turn signal bulbs utilize a 1129 size across both positions. The replacement chart covers 1950 to 1951 model 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 GMC P152 uses the 1129 bulb across both the front and rear turn signal positions for the 1950-1951 model years.
The 1129 is a dual-filament bulb, meaning it serves two lighting functions within a single unit, operating at 12 volts with a 21/5 watt output.
It is built on a BAY15d bayonet base, a two-pin offset base design that physically prevents incorrect insertion by positioning the pins at different heights.
The 1129 is an ANSI-recognized standard, indicating it meets defined performance and construction criteria recognized in both the United States and Canada.
The 1129 is described as a variant of the 1157, a widely used automotive bulb. While the two share the BAY15d base, they are not identical and are not confirmed as interchangeable within these specifications.