Buick Park Avenue high beam headlight bulbs use 9005 size while low beam headlight bulbs use 9006 size. Replacement chart data covers 1991 through 2005 vehicle 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.
The Buick Park Avenue uses the 9005 bulb for high beam headlights and the 9006 bulb for low beam headlights across all model years from 1991-2005.
The 9005 is a single-filament halogen bulb operating at 12V and 65W, built to the ANSI standard applicable in the United States and Canada, and fitted with a P20d base.
The 9006 is also a single-filament halogen bulb operating at 12V but rated at 55W, likewise conforming to the ANSI standard for the United States and Canada, and fitted with a P22d base.
Because the 9005 and 9006 share a similar body profile but carry different base types, the P20d and P22d bases are not interchangeable, meaning the high beam and low beam positions each accept only their designated bulb.
The 10-watt difference between the 9005 and 9006 reflects their intended functions, as the higher-wattage 9005 produces greater light output suited to high beam use, while the lower-wattage 9006 is calibrated for the controlled beam pattern required at low beam.
Both bulb types are governed by ANSI standards, which define consistent electrical and physical specifications, allowing bulbs from different manufacturers to remain interchangeable within each respective type.
The single-filament construction of both the 9005 and 9006 contrasts with dual-filament bulbs such as the 9004 or 9007, which handle both beam functions within a single housing. The Park Avenue uses separate bulbs for each function.
The fitment of the same bulb sizes across the entire 1991-2005 production span of the Park Avenue indicates that both headlight positions remained unchanged throughout the vehicle's production run.