GMC Brigadier Headlight Bulb Size

GMC Brigadier high beam and low beam headlight bulbs utilize H6024, H5001, H4651, H5006, and H4656 bulb sizes across different configurations. The replacement chart covers 1984 to 1988 production years with corresponding bulb size 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 Type	Shop
1988	H5001 (Tiltmaster)	Check Price
	H6024 (With 2 Headlamps)	Check Price
	H4651 (With 4 Headlamps)	Check Price
1985-1987	H6024 (With 2 Headlamps)	Check Price
1985-1987	H5001 (With 4 Headlamps)	Check Price
1984	H5001 (Tiltmaster)	Check Price

Low Beam Headlight

Years	Bulb Type	Shop
1988	H5006 (Tiltmaster)	Check Price
	H6024 (With 2 Headlamps)	Check Price
	H4656 (With 4 Headlamps)	Check Price
1985-1987	H6024 (With 2 Headlamps)	Check Price
1985-1987	H5006 (With 4 Headlamps)	Check Price
1984	H5006 (Tiltmaster)	Check Price

Bulb Specifications

Description	Type	Shop
ANSI standard (US & Canada). 4-inch square sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H5001	Check Price
ANSI standard (US & Canada). 7-inch round sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H6024	Check Price
ANSI standard (US & Canada). 4x6-inch rectangular sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H4651	Check Price
ANSI standard (US & Canada). 5.75-inch round sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H5006	Check Price
ANSI standard (US & Canada). 4x6-inch rectangular sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H4656	Check Price

Other Locations

Additional Notes

The GMC Brigadier headlight specifications cover four sealed beam bulb types across both high and low beam positions: H6024, H5001, H4651, H4656, and H5006. All five types conform to ANSI standards recognized in both the United States and Canada and operate at 12 volts.
All bulb types listed for the GMC Brigadier are sealed beam units, meaning the lens, reflector, and filament are fused into a single assembly. When a filament fails, the entire unit is replaced rather than an internal bulb component.
The H6024 is a 7-inch round sealed beam unit. It serves as both the high beam and low beam source on 2-headlamp configurations of the Brigadier across the 1985-1988 model years, making it the most broadly applied bulb type in these specifications.
The H5001 is a 4-inch square sealed beam unit used in the high beam position. It appears in 4-headlamp configurations for the 1985-1987 Brigadier and in the Tiltmaster variant for 1988, where it is paired with the H4651 rather than the H5006.
The H5006 is a 5.75-inch round sealed beam unit assigned to the low beam position. It is used in 4-headlamp configurations for the 1985-1987 Brigadier and in the 1984 Tiltmaster variant, where it pairs with the H5001 high beam unit.
The 1988 Tiltmaster variant uses a distinct bulb pairing not shared with other Brigadier configurations. Its high beam uses the H4651, a 4x6-inch rectangular sealed beam unit, while its low beam uses the H4656, also a 4x6-inch rectangular sealed beam unit. These two types are exclusive to the 1988 Tiltmaster within these specifications.
The H4651 and H4656 share the same 4x6-inch rectangular sealed beam form factor but serve different beam functions. Substituting one for the other would result in incorrect beam output, as high beam and low beam filament configurations differ between the two units.
The 1984 Brigadier specifications cover only the Tiltmaster variant, which uses the H5001 for high beam and the H5006 for low beam. No 2-headlamp or 4-headlamp configuration data is listed for that year.