The Chevrolet Laguna headlight bulb specifications include H4651 and H6024 sizes for high beam applications and H4652 and H6024 sizes for low beam functions. The replacement chart covers 1973 through 1976 model 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.
The H6024 is a 7-inch round sealed beam unit operating at 12V and conforming to ANSI standards recognized in both the US and Canada. Because the filament, lens, and reflector are fused into a single glass envelope, the entire unit is replaced rather than an internal bulb.
The H4651 and H4652 are both 4x6-inch rectangular sealed beam units operating at 12V under the same ANSI standard framework. The H4652 is a variant of the H4651, with the two types designated for different beam functions rather than different physical housings.
On the Chevrolet Laguna, the 1973-1975 model years used the H6024 for both high beam and low beam positions, meaning a single sealed beam type served both functions across those years.
The 1976 model year introduced a split-type rectangular headlight system, with the H4651 assigned to the high beam position and the H4652 to the low beam position. This represents a departure from the round sealed beam arrangement used in prior years.
The rectangular H4651 and H4652 units are not interchangeable with the round H6024, as the mounting, housing shape, and connector configurations differ between round and rectangular sealed beam formats under ANSI specifications.
The H4651 and H4652 are similarly not interchangeable with each other despite sharing the same physical housing format, as each is calibrated for a specific beam pattern, high or low, and substituting one for the other would produce incorrect light distribution.