Chevrolet Blazer Headlight Bulb Size

Chevrolet Blazer headlight bulb sizes include D3S, 9005, and H4666 options for high beam applications, with D3S, 9006, and H4666 sizes available for low beam functions. The replacement chart covers 1969 to 2020 model years with corresponding bulb specifications.

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

High Beam Headlight

Years	Bulb Size
2019-2020	D3S (With HID Headlamps)
1998-2003	9005
1995-1997	9005 (With Halogen Capsule Headlamps)
1995-1997	H4666 (With Sealed Beam Headlamps)
1992-1994	9005 (With Halogen Capsule Headlamps)
1992-1994	H6054 (With Sealed Beam Headlamps)
1989-1991	H6054 (With 2 Headlamps)
1989-1991	H4701 (With 4 Headlamps)
1987-1988	H6054 (With 2 Headlamps)
1987-1988	H4651 (With 4 Headlamps)
1969-1974	H6024

Low Beam Headlight

Years	Bulb Size
2019-2020	D3S (With HID Headlamps)
1998-2003	9006
1995-1997	9006 (With Halogen Capsule Headlamps)
1995-1997	H4666 (With Sealed Beam Headlamps)
1992-1994	9006 (With Halogen Capsule Headlamps)
1992-1994	H6054 (With Sealed Beam Headlamps)
1989-1991	H6054 (With 2 Headlamps)
1989-1991	H4703 (With 4 Headlamps)
1988	H6054 (With 2 Headlamps)
1988	H4656 (With 4 Headlamps)
1987	H6054 (With 2 Headlamps)
1987	H4652 (With 4 Headlamps)
1969-1974	H6024

Bulb Specifications

Description	Bulb Size
ECE standard (Europe & worldwide). Mercury-free HID (xenon) discharge bulb with PK32d-5 base and integral ignitor, for projector-type housings. 42V, 35W.	D3S
ANSI standard (US & Canada). Single-filament halogen bulb with P20d base. 12V, 65W.	9005
ANSI standard (US & Canada). Rectangular sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H4666
ANSI standard (US & Canada). 5x7-inch rectangular sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H6054
ANSI standard (US & Canada). 7-inch round sealed beam unit, variant. Not a replaceable bulb — the entire unit is replaced. 12V.	H4701
ANSI standard (US & Canada). 4x6-inch rectangular sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H4651
ANSI standard (US & Canada). 7-inch round sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H6024
ANSI standard (US & Canada). Single-filament halogen bulb with P22d base. 12V, 55W.	9006
ANSI standard (US & Canada). 7-inch round sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H4703
ANSI standard (US & Canada). 4x6-inch rectangular sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H4656
ANSI standard (US & Canada). 4x6-inch rectangular sealed beam unit, variant of H4651. Not a replaceable bulb — the entire unit is replaced. 12V.	H4652

Other Locations

Additional Notes

The D3S is an ECE-standard, mercury-free HID (xenon) discharge bulb rated at 42V and 35W, fitted with a PK32d-5 base and an integral ignitor. It is designed exclusively for projector-type housings. The Chevrolet Blazer uses this bulb for both high and low beam functions in 2019-2020 models equipped with HID headlamps, meaning a single bulb type serves both beam positions in those configurations.
The 9005 and 9006 are both ANSI-standard single-filament halogen bulbs operating at 12V, but they differ in wattage and base type. The 9005 carries a P20d base and draws 65W for high beam use, while the 9006 uses a P22d base and draws 55W for low beam use. These two bulbs are not interchangeable despite their physical similarity, as the base configurations are distinct.
The Blazer used the 9005 for high beam and the 9006 for low beam across the 1998-2003 model years, as well as in 1995-1997 models fitted with halogen capsule headlamps rather than sealed beam units.
Sealed beam units such as the H6054, H4666, H6024, H4701, H4651, H4703, H4656, and H4652 are not replaceable bulbs. When one of these units fails, the entire headlamp assembly is replaced rather than an internal component.
The H6054 is a 5x7-inch rectangular sealed beam unit used on the Blazer in both two-headlamp and four-headlamp configurations from 1991-1994, covering both high and low beam positions in two-headlamp setups. In four-headlamp setups, dedicated beam-specific sealed beam units were used alongside or instead of it.
In four-headlamp configurations from 1987-1991, the Blazer used separate sealed beam units for high and low beams. The high beam units were the H4651 (1987-1988) and H4701 (1989-1991), while the low beam units were the H4652 (1987), H4656 (1988), and H4703 (1989-1991). These units are not interchangeable with one another despite sharing the same general sealed beam format.
The H6024 is a 7-inch round sealed beam unit used on the Blazer from 1969-1974 for both high and low beam positions. Like all sealed beam types in these specifications, it operates at 12V and is replaced as a complete unit.
The 1995-1997 Blazer models present a dual-fitment situation, where either sealed beam or halogen capsule headlamps were installed depending on the trim or configuration. The sealed beam variants used the H4666 unit, while the halogen capsule variants used the 9005 for high beam and the 9006 for low beam. These two headlamp systems are not cross-compatible.