The Chevrolet P60 headlight bulb specifications include H6024 and H4651 sizes for high beam applications and H6024 and H4656 sizes for low beam applications. The replacement chart covers 1983 through 1988 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 Chevrolet P60 uses sealed beam headlight units across all listed model years (1983-1988), meaning the entire unit is replaced rather than an individual bulb filament or capsule.
Three sealed beam types appear in these specifications: the H6024, a 7-inch round unit, and the H4651 and H4656, both 4x6-inch rectangular units. All three operate at 12V and conform to ANSI standards applicable in the United States and Canada.
The H6024 round sealed beam serves as both a high beam and low beam option across all listed years, making it the only unit in these specifications that covers both functions.
The H4651 and H4656 are physically identical in form factor, both being 4x6-inch rectangular sealed beams, but they are not interchangeable. The H4651 is designated for high beam use, while the H4656 is designated for low beam use.
All headlight configurations in these specifications are noted as applying to vehicles equipped with 4 headlamps, indicating a quad-headlamp arrangement for the P60 across the 1983-1988 model years.
In a 4-headlamp system using rectangular sealed beams, the H4651 (high beam) and H4656 (low beam) occupy separate housings, which is a characteristic of traditional North American sealed beam quad-lamp setups rather than a combined high/low beam design.
The H6024 round sealed beam is a long-established North American standard unit. Its 7-inch round format was among the most widely used sealed beam specifications in the automotive industry, contributing to broad availability across the market.
Because all three bulb types in these specifications are sealed beam units governed by ANSI standards, physical fitment is determined by the standardized form factor rather than manufacturer-specific housing geometry, though beam function designation must still be matched correctly.