The Mack Granite (GU) headlight bulb size chart specifies high beam and low beam bulb configurations, with high beam options including H6024 and 9005XS sizes and low beam options including H6024 and 9006XS sizes. The replacement chart covers vehicle production data spanning 2011 to 2022.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Mack Granite (GU) uses two distinct headlamp system types across the 2011-2019 model years: sealed beam and halogen capsule. Each system requires a different bulb type for both high and low beam functions, and the two systems are not interchangeable with one another.
The H6024 is a 7-inch round sealed beam unit operating at 12V. It serves as both the high beam and low beam bulb in sealed beam-equipped Granite (GU) vehicles, as the sealed beam design integrates the lens, reflector, and filament into a single assembly. The entire unit is replaced rather than an internal bulb.
Vehicles fitted with halogen capsule headlamps use separate bulb types for each beam function. The 9005XS handles high beam duties, while the 9006XS handles low beam duties. These two bulbs are not interchangeable despite sharing the same base style.
The 9005XS is a single-filament halogen bulb rated at 12V and 65W. It follows the ANSI standard and features a straight 180-degree base configuration.
The 9006XS is also a single-filament halogen bulb with a straight 180-degree base, rated at 12V and 55W. Its wattage is 10W lower than the 9005XS, reflecting the reduced output typical of low beam applications.
Both the 9005XS and 9006XS carry ANSI designations valid in the United States and Canada, as does the H6024. All three bulbs operate on a 12V electrical system.
The straight 180-degree base shared by the 9005XS and 9006XS is a physical characteristic of the XS variants within their respective bulb families. Despite this shared base geometry, the differing wattage and internal filament orientation mean substituting one for the other is not supported by the specifications.