The Eagle Summit brake light requires a 2057 bulb size for proper installation and function. Data for the specified component covers the range from 1989 through 1992.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 2057 bulb is the sole brake light specification for the Eagle Summit across the 1989-1992 model years.
The 2057 is a dual-filament bulb operating at 12V with a BAY15d bayonet base, drawing 26.9W on the high-filament circuit and 8W on the low-filament circuit, making it suitable for combined stop and tail light functions.
The 2057 is a brighter variant of the 1157, sharing the same BAY15d base, which means the two bulbs are physically interchangeable in many sockets, though their light output differs.
The Center High Mount Stop Light (CHMSL) on the Eagle Summit used three different bulb specifications across the 1990-1992 model years, with no single bulb type shared between all three years.
The 1991 Eagle Summit CHMSL uses the 1156, a single-filament bulb with a BA15s bayonet base rated at 12V and 21W, which is a higher wattage than the CHMSL bulbs specified for the 1990 and 1992 model years.
The 1992 Eagle Summit CHMSL uses the 904, a miniature wedge bulb in a T10 form factor rated at 12V and 8W, which is physically incompatible with the BA15s bayonet socket required by the 1991 specification.
The 1990 Eagle Summit CHMSL uses the 912, a T15 wedge bulb rated at 12V and 12W, described as a variant of the 921, meaning the two share a wedge base but may differ in wattage or filament design.
The T10 (904) and T15 (912) wedge bases used in the 1992 and 1990 CHMSL positions respectively are not interchangeable with each other or with the BA15s bayonet base of the 1156 used in 1991, making year-specific fitment a relevant consideration for the CHMSL position.
All four bulb types in these specifications conform to ANSI standards applicable in both the United States and Canada.
The wattage across the CHMSL bulbs ranges from 8W (904) to 21W (1156), a spread that reflects meaningfully different electrical loads depending on the model year.