The Mazda GLC uses H6054 and H6024 bulb sizes for both high beam and low beam headlight applications. The replacement chart covers vehicle production spanning 1977 to 1985 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 Mazda GLC uses two sealed beam headlight types across its model years: the H6054 and the H6024. Both are ANSI-standardized units sold in the US and Canadian markets and operate on 12V electrical systems.
The H6054 is a 5x7-inch rectangular sealed beam unit. Like all sealed beam designs, the entire housing, lens, and filament assembly form a single unit, meaning the whole assembly is replaced rather than an internal bulb.
The H6024 is a 7-inch round sealed beam unit. It shares the same sealed beam construction principle as the H6054 and is likewise replaced as a complete unit.
The Mazda GLC used the H6024 round sealed beam for both high and low beam functions during the 1977-1978 model years.
From 1979-1985, both the high beam and low beam positions transitioned to the H6054 rectangular sealed beam unit. The 1982 year is included in this range based on the specifications provided.
The H6054 and H6024 are not interchangeable. The rectangular and round form factors are physically distinct, and substituting one for the other is not compatible with the housing designed for each type.
Because both the high beam and low beam positions share the same bulb type within any given model year, a single sealed beam unit serves dual-function headlight systems on the GLC for those years.