Pontiac Grand Safari Headlight Bulb Size

The Pontiac Grand Safari headlight bulb size chart specifies high beam and low beam bulb sizes, including H4651, H5001, H4656, H4652, and H5006 configurations for this vehicle model. The replacement chart covers 1971 through 1978 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
1975-1978	H4651
1971-1974	H5001

Low Beam Headlight

Years	Bulb Size
1978	H4656
1976-1977	H4652
1975	H4656
1971-1974	H5006

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). 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

The Pontiac Grand Safari uses sealed beam headlight units across all model years covered in the specifications, meaning the entire lens-reflector-filament assembly is replaced as one unit rather than swapping an internal bulb.
All sealed beam types listed operate on 12V and conform to ANSI standards recognized in both the United States and Canada.
The H4651 and H4656 are both 4x6-inch rectangular sealed beam units, with the H4651 serving the high beam position and the H4656 serving the low beam position. Despite their similar physical format, they are not interchangeable due to differing beam patterns and filament configurations specific to each function.
The H4652, used in the low beam position for 1976-1977, is a variant of the H4651 in the same 4x6-inch rectangular format. Its classification as a variant indicates a functional difference from the H4651, making direct substitution between the two inadvisable without confirming compatibility.
For the 1971-1974 model years, the Pontiac Grand Safari used 4-inch square sealed beam units (H5001) for the high beam and 5.75-inch round sealed beam units (H5006) for the low beam, representing a physically distinct headlight format from the rectangular units used in later years.
The shift from round and square sealed beam formats (1971-1974) to rectangular sealed beam formats (1975-1978) reflects a change in headlight housing design between those production periods, meaning parts from one era are not physically compatible with housings from the other.
The low beam specification for 1975 and 1978 is the H4656, while 1976-1977 uses the H4652. Although both are 4x6-inch rectangular units, the year-specific fitment means the low beam type is not uniform across the entire 1975-1978 range.
The high beam specification remains consistent at H4651 for the full 1975-1978 period, and at H5001 for the full 1971-1974 period, indicating no variation in the high beam position within either of those two production spans.