Plymouth Gran Fury Headlight Bulb Size

Additional Notes

• The Plymouth Gran Fury uses sealed beam headlight units across all listed model years, meaning the entire lens-reflector-filament assembly is replaced as one unit rather than replacing a separate bulb inside a housing.
• All sealed beam types specified for the Gran Fury operate on 12V and conform to ANSI standards recognized in both the United States and Canada.
• The H4651 is a 4x6-inch rectangular sealed beam unit and serves as the high beam headlight for the Gran Fury across the 1980-1989 model years, making it the most consistently used unit in these specifications.
• The H4652, a variant of the H4651, shares the same 4x6-inch rectangular sealed beam format but is designated for low beam use. It appears in the low beam position for most of the 1980-1989 range, though 1986 and 1989 use the H4656 instead, indicating that H4652 and H4656 are not interchangeable despite their physical similarity.
• The H6024 is a 7-inch round sealed beam unit used in both the high beam and low beam positions for the 1975-1977 model years. Because both positions share the same part number in those years, the Gran Fury used a dual-purpose round sealed beam configuration during that period.
• The 1972-1974 model years use two distinct sealed beam units: the H5001, a 4-inch square unit for high beam, and the H5006, a 5.75-inch round unit for low beam, reflecting a mixed-shape headlight arrangement.
• The H4656 appears only in the low beam position for the 1986 and 1989 Gran Fury, while the high beam for those same years retains the H4651. This split fitment means the two 4x6-inch rectangular units in those years are position-specific and not interchangeable with each other.
• Because all units across all listed years are sealed beams governed by ANSI standards, physical form factor and ANSI designation together determine correct fitment, and substituting one sealed beam type for another of a different designation is not supported by these specifications.