Cadillac Series 75 Fleetwood Headlight Bulb Size

The Cadillac Series 75 Fleetwood headlight bulb specifications include high beam sizes H5001, H6024, and H6006, along with low beam sizes H5006, H6024, and H6006 in various bulb configurations. The replacement chart covers vehicle production years spanning 1950 to 1964 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
1958-1964	H5001
1953-1957	H6024
1950-1952	H6006

Low Beam Headlight

Years	Bulb Size
1958-1964	H5006
1953-1957	H6024
1950-1952	H6006

Bulb Specifications

Description	Bulb Size
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). 5.75-inch round sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V.	H5006

Other Locations

Additional Notes

The H5001 and H5006 are the most frequently specified bulb types across these specifications, with the H5001 covering high beam duties and the H5006 covering low beam duties on the Cadillac Series 75 Fleetwood for model years 1958-1964.
The H5001 is a 4-inch square sealed beam unit operating at 12V and conforming to ANSI standards for the US and Canada. As a sealed beam design, the entire unit is replaced rather than an internal filament or capsule.
The H5006 is a 5.75-inch round sealed beam unit, also rated at 12V and built to the same ANSI standard. It pairs with the H5001 in a split high/low beam configuration for the 1958-1964 model years.
For model years 1953-1957, both the high beam and low beam positions share a single bulb type, the H6024, a 7-inch round sealed beam unit rated at 12V. A single unit type serving both functions indicates a dual-filament sealed beam design.
The H6006, a 5x7-inch rectangular sealed beam unit rated at 12V, was specified for both the high beam and low beam positions across the 1950-1952 model years, again reflecting a dual-filament arrangement within one sealed unit.
All four bulb types in these specifications are sealed beam units, meaning the reflector, lens, and filament are fused into a single non-serviceable assembly. Replacement requires swapping the entire sealed unit.
The shift from H6006 rectangular units to H6024 round units between the 1952 and 1953 model years, and then to separate H5001 and H5006 units from 1958 onward, reflects changes in headlamp housing geometry across those production periods.
Because the H5001 and H5006 are distinct part numbers with different physical sizes, the two are not interchangeable despite both being used on the same vehicle for the 1958-1964 model years. Installing the incorrect unit in either position would result in a fitment mismatch.