The BMW 733i uses an H5001 bulb size for high beam headlight operation and an H5006 bulb size for low beam headlight operation. The replacement chart covers vehicle production spanning 1978 to 1984 with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The BMW 733i used two distinct sealed beam headlight units across its 1978-1984 production span: the H5001 for high beam and the H5006 for low beam.
The H5001 is a 4-inch square sealed beam unit operating at 12V, conforming to ANSI standards recognized in the United States and Canada. Because it is a sealed beam design, the entire unit is replaced rather than an internal filament or capsule.
The H5006 is a 5.75-inch round sealed beam unit, also rated at 12V and built to the same ANSI standard. Like the H5001, it requires full unit replacement when it fails.
The square profile of the H5001 and the round profile of the H5006 make the two units physically incompatible with each other, and neither can serve as a substitute for the other in its respective housing.
Both the H5001 and H5006 remained unchanged across all seven model years covered by the specifications, indicating a consistent headlight fitment throughout the entire 1978-1984 production range of the BMW 733i.
Sealed beam technology integrates the filament, reflector, and lens into a single glass unit. This construction differs from later halogen or composite headlight systems, where only the bulb capsule is replaced within a separate housing.
The ANSI standardization of both units means that H5001 and H5006 replacements from any manufacturer meeting that standard are dimensionally and electrically equivalent to the original equipment.