GMC 250 high beam and low beam headlight bulbs utilize H6024, H5001, H5006, and H6006 bulb sizes across various configurations. The replacement chart covers 1951 through 1959 production years 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 H6006 is the most frequently specified bulb across the GMC 250's headlight data, covering both high and low beam positions for the 1951-1955 model years. It is a 5x7-inch rectangular sealed beam unit rated at 12V and built to the ANSI standard applicable in the US and Canada.
The H6024 appears across both high and low beam positions for the 1956-1957 model years, and again for 1958-1959 on vehicles equipped with a two-headlamp configuration. It is a 7-inch round sealed beam unit, also rated at 12V and conforming to the same ANSI standard.
All bulb types listed for the GMC 250 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.
For the 1958-1959 model years, the GMC 250 headlight specifications branch into two distinct configurations depending on whether the vehicle was built with two or four headlamps, resulting in different bulb requirements for each setup.
On the GMC 250 with a four-headlamp setup for 1958-1959, the high beam position uses the H5001, a 4-inch square sealed beam unit, while the low beam position uses the H5006, a 5.75-inch round sealed beam unit. These two types are not interchangeable with each other despite both serving the four-lamp system.
The H5001 and H5006 are exclusive to the four-headlamp configuration of 1958-1959 and do not appear in any other model year within these specifications, making them distinct from the H6006 and H6024 types that span multiple years.
All four sealed beam types listed across the GMC 250 specifications operate at 12V and conform to the ANSI standard for the US and Canadian markets, indicating a shared electrical compatibility across the range despite differences in physical form.