The GMC PM152 front and rear turn signal bulbs utilize either 1073 or 1129 size bulbs depending on production specifications. The replacement chart covers 1952 through 1957 model years with corresponding bulb size data.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The GMC PM152 uses two bulb types across its front and rear turn signal positions: the 1073 and the 1129, both of which conform to ANSI standards recognized in the United States and Canada.
The 1129 bulb is the more widely used of the two across the PM152 specifications, appearing in both the front and rear turn signal positions for the 1952, 1954, and 1955 model years.
The 1073 bulb applies exclusively to the 1957 model year, serving both the front and rear turn signal positions on the GMC PM152.
The 1129 is a dual-filament bulb operating at 12 volts with a 21/5W output, mounted on a BAY15d bayonet base, which features offset pins to prevent incorrect installation.
The 1073 is a single-filament bulb operating at 12 volts with a 13W output, mounted on a BA15s bayonet base, which uses a single center pin for alignment.
The BA15s base of the 1073 and the BAY15d base of the 1129 are physically distinct and are not interchangeable, as the pin configurations differ between single- and dual-filament bayonet bases.
The 1073 is described as a lower wattage variant of the 1156, while the 1129 is described as a variant of the 1157, indicating a family relationship in base design but differences in wattage output.
Because the 1957 PM152 uses the single-filament 1073 rather than the dual-filament 1129, substituting a 1157-family bulb in that position would introduce an incompatible base type and an additional filament circuit.