Oldsmobile Cutlass Supreme Headlight Bulb Size

Additional Notes

• The Oldsmobile Cutlass Supreme transitioned through several distinct headlight technologies across its production span, moving from sealed beam units in earlier years to replaceable halogen capsule bulbs in later model years.
• The 9005 and 9006 bulbs, used in the 1989-1991 Cutlass Supreme for high and low beam respectively, are single-filament halogen bulbs operating at 12V. The 9005 draws 65W and uses a P20d base, while the 9006 draws 55W and uses a P22d base. These are replaceable bulbs, meaning only the bulb itself is swapped rather than the entire headlight housing.
• The 9004 bulb, specified for 1987 models equipped with halogen capsule headlamps, is a dual-filament halogen unit operating at 12V with a P29t base and a 65W/45W rating, handling both high and low beam functions within a single bulb.
• The 1987 Cutlass Supreme carried two distinct headlight system configurations: sealed beam units using H4651 (high beam) and H4652 (low beam), or halogen capsule headlamps using the 9004 bulb for both functions. These systems are not interchangeable, and the correct bulb type depends on which headlamp system the vehicle was built with.
• Sealed beam units such as the H4651, H4652, H4656, H6054, H6024, H5001, and H5006 are not replaceable bulbs. When a sealed beam unit fails, the entire unit is replaced as a single assembly. All sealed beam types in these specifications operate at 12V.
• The H4651 and H4652 are both 4x6-inch rectangular sealed beam units under the ANSI standard, with H4652 considered a variant of H4651. Despite their physical similarity, they serve different beam functions and are not interchangeable between high and low beam positions.
• The H5001 and H5006 sealed beam units, used on the 1967-1972 Cutlass Supreme, are round units of different sizes. The H5001 is a 4-inch square sealed beam used for high beam, while the H5006 is a 5.75-inch round sealed beam used for low beam.
• The 1974-1975 Cutlass Supreme used the H6024, a 7-inch round sealed beam unit, for both high and low beam positions, while the 1978-1979 models used the H6054, a 5x7-inch rectangular sealed beam unit, for both positions.