BMW 2800 front turn signal bulbs measure 1157 in size, while rear turn signal bulbs measure 1156, with each bulb type serving distinct lighting functions on the vehicle. The replacement chart covers 1969 to 1971 production years and details bulb size specifications for turn signal applications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The BMW 2800 uses the 1157 bulb for the front turn signal across the 1969-1971 model years.
The 1157 is a dual-filament bulb, meaning it serves two lighting functions within a single housing, operating at 21W on the primary filament and 5W on the secondary filament.
The 1157 uses a BAY15d bayonet base, which features two offset pins to ensure correct orientation during installation and prevent interchange with single-filament sockets.
The rear turn signal on the BMW 2800 uses the 1156 bulb across the 1969-1971 model years.
The 1156 is a single-filament bulb rated at 21W, designed exclusively for applications requiring one lighting function per socket.
The 1156 uses a BA15s bayonet base, which has two symmetrically placed pins, distinguishing it physically from the BAY15d base of the 1157.
Although the 1157 and 1156 share the same 12V operating voltage and a similar physical profile, their base pin configurations differ, making them non-interchangeable despite their visual resemblance.
Both the 1157 and 1156 are ANSI standardized bulbs recognized in the United States and Canada, indicating conformance to a defined set of electrical and physical tolerances.