Buick LeSabre Headlight Bulb Size

The Buick LeSabre headlight bulb specifications include high beam sizes 9005, H4651, and H5001, along with low beam sizes 9006, H4652, and H4656 for this vehicle model. The replacement chart covers 1959 through 2005 production years with corresponding bulb size data.

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
1991-2005	9005
1987	9005
1976-1986	H4651
1959-1975	H5001

Low Beam Headlight

Years	Bulb Size
1991-2005	9006
1987	9006
1986	H4652
1985	H4656
1984	H4652
1983	H4656
1982	H4652
1981	H4656
1978-1980	H4652
1976-1977	H4656
1959-1975	H5006

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament halogen bulb with P20d base. 12V, 65W.	9005
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). 4-inch square sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H5001
ANSI standard (US & Canada). Single-filament halogen bulb with P22d base. 12V, 55W.	9006
ANSI standard (US & Canada). 4x6-inch rectangular sealed beam unit, variant of H4651. Not a replaceable bulb — the entire unit is replaced. 12V.	H4652
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). 5.75-inch round sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H5006

Other Locations

Additional Notes

The Buick LeSabre uses three distinct high beam bulb types across its production span: the H5001 sealed beam unit from 1959-1975, the H4651 sealed beam unit from 1976-1986, and the 9005 halogen bulb from 1987-2005 (excluding 1988-1990).
The 9005 is a single-filament halogen bulb rated at 12V and 65W with a P20d base, conforming to ANSI standards for the US and Canadian markets. Its counterpart, the 9006 low beam bulb, shares the same voltage rating but draws less power at 55W and uses a P22d base.
The P20d and P22d bases of the 9005 and 9006 are not interchangeable. Although the two bulbs are physically similar, their base designs differ specifically to prevent incorrect installation, as swapping high and low beam bulbs would produce improper light output and road glare.
The H4651 high beam and H4652 low beam are both 4x6-inch rectangular sealed beam units operating at 12V. The H4652 is classified as a variant of the H4651, though the two serve different beam functions and are not substitutes for one another.
The Buick LeSabre (1976-1986) used H4656 sealed beam units for the low beam in certain model years, specifically 1976-1977, 1981, 1983, and 1985, while other years in that range used the H4652. Both are 4x6-inch rectangular sealed beam units, but they are distinct part numbers and are not listed as interchangeable in these specifications.
Sealed beam units, including the H5001, H4651, H4652, H4656, H5006, and H4651, are not bulb-replacement designs. When a sealed beam fails, the entire housing unit is replaced rather than an internal filament or capsule.
The H5001 high beam and H5006 low beam, used from 1959-1975, are 4-inch square and 5.75-inch round sealed beam units respectively. The difference in physical form between the two reflects their separate optical functions within the same headlight system.
All bulb types listed across the full production range of the LeSabre conform to ANSI standards applicable to the US and Canadian markets, and all operate on a 12V electrical system.