The Buick GS 455 uses an H5001 bulb size for high beam headlights and an H5006 bulb size for low beam headlights. The replacement chart covers vehicle production years spanning 1970 to 1972 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 Buick GS 455 uses the H5001 sealed beam unit for high beam headlights across the 1970-1972 model years.
Low beam headlights on the same vehicle across the same 1970-1972 span use the H5006 sealed beam unit.
The H5001 is a 4-inch square sealed beam unit operating at 12V and conforming to ANSI standards recognized in both the United States and Canada.
The H5006 is a 5.75-inch round sealed beam unit, also rated at 12V and held to the same ANSI standard as the H5001.
Both the H5001 and H5006 are sealed beam units, meaning the lens, reflector, and filament are fused into a single assembly. When the filament fails, the entire unit requires replacement rather than an internal bulb swap.
The square format of the H5001 and the round format of the H5006 are not interchangeable, as the two units differ in shape and serve distinct beam functions within the headlight system.