Chevrolet C-Series Pickup brake bulb sizes include 1157, 3057, and 2057, with a center high mount stop light bulb size of 921. The replacement chart covers vehicle production years spanning 1975 to 2000.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Chevrolet C-Series Pickup brake light specifications cover model years 1975 through 2000, with four distinct bulb types appearing across that span: the 1157, 3057, 2057, and 198.
The 3057 is the most frequently specified brake bulb across this range, covering the 1990-1996 and 1998 model years. It is a dual-filament T25 wedge bulb rated at 12V with a high-filament draw of 27W and a low-filament draw of 7W.
The 1157 is the second most common type, specified for 1979-1982, 1997, 1999, and 2000. It uses a BAY15d bayonet base and operates at 12V with filament ratings of 21W and 5W.
The 2057 shares the same BAY15d bayonet base as the 1157 but draws higher wattage at 26.9W and 8W respectively, making it a physically similar yet electrically distinct bulb. It is specified for 1983-1986 and 1988-1989.
Despite the physical base compatibility between the 1157 and 2057, substituting one for the other alters the electrical load on the circuit, which can affect turn signal flash rates and may trigger fault indicators on vehicles with load-sensitive systems.
The 198 is a miniature T5 wedge bulb rated at only 12V and 2W, a single-filament type used exclusively on the 1975-1978 model years. Its low wattage output distinguishes it significantly from the dual-filament bulbs used in later years.
The 3057 is a T25 wedge type, while the 1157 and 2057 use a BAY15d bayonet base. These two base types are not interchangeable, meaning socket compatibility must be confirmed before substitution.
The Center High Mount Stop Light (CHMSL) on the Chevrolet C-Series Pickup uses the 921 bulb for model years 1993-2000. The 921 is a single-filament T15 wedge bulb rated at 12V and 16W.
The 921 wedge base used in the CHMSL is a different socket format from the BAY15d bayonet base of the 1157 and 2057, and also differs from the T25 wedge format of the 3057, making cross-application fitment incompatible.
All five bulb types listed in these specifications conform to ANSI standards applicable in both the United States and Canada.