Kenworth C500 Headlight Bulb Size

The Kenworth C500 headlight bulb specifications include high beam sizes H4651 and H5001, along with low beam sizes H4652, H4656, and H5006 for this heavy-duty truck model. The replacement chart covers 1981 through 1997 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 Type	Shop
1984-1997	H4651	Check Price
1981-1983	H5001	Check Price

Low Beam Headlight

Years	Bulb Type	Shop
1994-1997	H4652	Check Price
1992-1993	H4656	Check Price
1990-1991	H4652	Check Price
1989	H4656	Check Price
1988	H4652	Check Price
1985-1987	H4656	Check Price
1984	H4652	Check Price
1981-1983	H5006	Check Price

Bulb Specifications

Description	Type	Shop
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). 4-inch square sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H5001	Check Price
ANSI standard (US & Canada). 4x6-inch rectangular sealed beam unit, variant of H4651. Not a replaceable bulb — the entire unit is replaced. 12V.	H4652	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
ANSI standard (US & Canada). 5.75-inch round sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H5006	Check Price

Other Locations

Additional Notes

The Kenworth C500 uses sealed beam headlight units across all listed model years from 1981-1997, meaning the entire lens-reflector-filament assembly is replaced as one unit rather than swapping an internal bulb.
All sealed beam types specified for the C500 operate on 12V and conform to ANSI standards recognized in both the United States and Canada.
The H4651 and H4652 are both 4x6-inch rectangular sealed beam units, with the H4652 classified as a variant of the H4651. The H4651 serves the high beam position while the H4652 serves the low beam position, so the two are not interchangeable despite their physical similarity.
The H4656 is also a 4x6-inch rectangular sealed beam unit used in the low beam position on certain C500 model years, and it shares the same physical format as the H4651 and H4652 without being a direct substitute for either.
The Kenworth C500 from 1984-1997 uses 4x6-inch rectangular sealed beam units for the high beam, while the 1981-1983 model years use the H5001, a 4-inch square sealed beam unit, making these earlier years physically incompatible with the rectangular format used afterward.
The low beam headlight specification for the 1981-1983 C500 is the H5006, a 5.75-inch round sealed beam unit, which differs in both shape and size from all low beam units specified for the 1984-1997 model years.
The low beam position on the C500 shows variation between the H4652 and H4656 across different years within the 1984-1997 range, indicating that not all years within this span share an interchangeable low beam unit even though both types share the same 4x6-inch rectangular format.