The GMC PM252 uses H6006 bulb size for both high beam and low beam headlight applications. The replacement chart covers 1952 to 1955 vehicle 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 GMC PM252 uses the H6006 bulb size across both the high beam and low beam headlight positions for the 1952-1955 model years.
The H6006 is an ANSI-standard sealed beam unit recognized in both the United States and Canada, operating at 12 volts.
Sealed beam units such as the H6006 are self-contained assemblies in which the filament, reflector, and lens are fused into a single housing, meaning the entire unit is replaced rather than an internal bulb.
The H6006 follows a 5x7-inch rectangular form factor, which is a standardized size shared across many vehicle applications of that era, making cross-brand fitment possible in some cases.
Because the high beam and low beam positions on the PM252 both use the H6006, the same sealed beam unit serves both functions, which was a common arrangement in single-headlight systems where one sealed beam contained dual filaments or where separate units were not yet in use.
The shared H6006 specification across all four model years means a single replacement unit is compatible with the full 1952-1955 range of the GMC PM252 for both headlight positions.