Pontiac Catalina Headlight Bulb Size

The Pontiac Catalina high beam headlight bulb sizes include H4651, H5001, and H6024, while low beam headlight bulb sizes consist of H4656, H4652, and H5006 across various model generations. The replacement chart covers 1950 through 1981 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 Size
1977-1981	H4651
1958-1976	H5001
1955-1957	H6024
1950-1954	H6006

Low Beam Headlight

Years	Bulb Size
1981	H4656
1977-1980	H4652
1958-1976	H5006
1955-1957	H6024
1950-1954	H6006

Bulb Specifications

Description	Bulb Size
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). 7-inch round sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H6024
ANSI standard (US & Canada). 5x7-inch rectangular sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H6006
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
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

All headlight bulb types specified for the Pontiac Catalina across its full production range are sealed beam units, meaning the entire lens-and-filament assembly is replaced as one piece rather than a separate bulb being swapped within a housing.
Every sealed beam type listed operates at 12 volts and conforms to ANSI standards recognized in both the United States and Canada.
The H5001 is a 4-inch square sealed beam unit used for the high beam position on the Pontiac Catalina from 1958-1977, making it the most frequently specified bulb type across the Catalina's headlight history. Its paired low beam counterpart for 1958-1977 is the H5006, a 5.75-inch round sealed beam unit.
From 1977-1981, the high beam position transitioned to the H4651, a 4x6-inch rectangular sealed beam unit. The low beam position for those years used related 4x6-inch rectangular units, specifically the H4652 for 1977-1980 and the H4656 for 1981, both of which share the same physical format as the H4651 but are distinct part numbers serving different beam functions.
The H4652 is formally described as a variant of the H4651. Despite their shared physical format and close designation, the two are not interchangeable, as each is rated for a specific beam position.
For 1955-1957, both the high beam and low beam positions share the same bulb type, the H6024, a 7-inch round sealed beam unit. This dual-beam application within a single unit differs from the split high/low beam arrangement used in later years.
The 1950-1954 Catalina used the H6006, a 5x7-inch rectangular sealed beam unit, for both beam positions. Like the H6024, this reflects an era when a single sealed beam served both functions rather than separate units for high and low beams.
The shift from rectangular H6006 units in 1950-1954 to round H6024 units in 1955-1957, and then to square H5001 and round H5006 pairings from 1958 onward, reflects successive changes in the ANSI sealed beam formats specified for the Catalina over its production life.