Chevrolet Blazer Brake Bulb Size

The Chevrolet Blazer brake light utilizes 7440, 3057, 2057, and 198 bulb sizes depending on the specific configuration of the vehicle. Available data for the lighting components spans from 1969 through 2022.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
2022	7440
2019-2020	7440
1993-2003	3057
1992	3057 (With Halogen Capsule Headlamps)
1992	2057 (With Sealed Beam Headlamps)
1987-1991	2057
1969-1974	198

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament wedge bulb (T20). 12V, 21W.	7440
ANSI standard (US & Canada). Dual-filament wedge bulb (T25). 12V, 27W/7W.	3057
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Brighter variant of 1157. 12V, 26.9W/8W.	2057
ANSI standard (US & Canada). Miniature wedge bulb (T5). 12V, 2W.	198

Other Locations

Additional Notes

The 3057 bulb is the most frequently specified brake bulb across the Chevrolet Blazer model range, covering the 1993-2003 and 1992 (With Halogen Capsule Headlamps) model years. It is a dual-filament wedge bulb rated at 12V with a high-beam filament of 27W and a low-beam filament of 7W, conforming to the T25 wedge form factor under the ANSI standard for the US and Canada markets.
The 7440 is a single-filament T20 wedge bulb rated at 12V and 21W, specified for the Chevrolet Blazer in 2019, 2020, and 2022. Unlike the dual-filament bulbs used in earlier model years, the 7440 carries only one filament, meaning it serves a dedicated function rather than combining stop and tail lighting in a single unit.
The 2057 bulb uses a BAY15d bayonet base rather than a wedge base, distinguishing it physically from the 3057 and 7440. It is a dual-filament bulb rated at 12V with filaments of 26.9W and 8W, and it is noted as a brighter variant of the 1157. It is specified for the 1987-1991 model years and for the 1992 model year with Sealed Beam Headlamps.
The 1992 Chevrolet Blazer carries two separate brake bulb specifications depending on headlamp configuration. Vehicles equipped with Halogen Capsule Headlamps use the 3057, while those equipped with Sealed Beam Headlamps use the 2057. These two bulbs are not interchangeable due to their differing base types, wedge versus bayonet, and wattage ratings.
The 198 is a miniature T5 wedge bulb rated at 12V and 2W, specified for the 1969-1974 model years. At 2W, its output is substantially lower than the other bulb types in these specifications, reflecting a different brake lighting application or circuit design used during that period.
The transition from the 2057 to the 3057 between the 1992 and 1993 model years represents a base-type change from BAY15d bayonet to T25 wedge. These two bulbs are not cross-compatible despite both being dual-filament 12V units, as their physical mounting interfaces differ entirely.
The 3057 and 2057 are both dual-filament bulbs, meaning each contains a high-wattage filament for the brake function and a lower-wattage filament for the tail light function within a single housing. The 7440, by contrast, is single-filament and does not share this combined stop-and-tail capability.
All four bulb types listed across these specifications conform to ANSI standards applicable to the US and Canada markets, indicating standardized electrical and photometric performance requirements shared across the bulb designations regardless of their differing base types, filament counts, or wattage ratings.