Oldsmobile Firenza Headlight Bulb Size

Additional Notes

• The 1982 Oldsmobile Firenza uses the H6054 sealed beam unit for both high and low beam positions, making it the only model year in these specifications where a single bulb type serves both functions.
• The H6054 is a 5x7-inch rectangular sealed beam unit rated at 12V. As a sealed beam design, the entire unit is replaced rather than an internal filament or capsule.
• The H4651 and H4652 are both 4x6-inch rectangular sealed beam units operating at 12V. They share the same physical housing format but are distinct part numbers, with H4652 classified as a variant of H4651.
• Because H4651 and H4652 are separate designations despite their shared format, substituting one for the other without confirming compatibility is not supported by these specifications.
• The 1983 and 1985-1986 model years differ in their low beam assignment despite sharing the same high beam bulb. The 1983 Firenza uses H4652 for low beam, while the 1985-1986 models use H4656, a separate 4x6-inch sealed beam unit.
• The 1988 Firenza departs from the sealed beam format used in all prior years, with the high beam position switching to the 9005 and the low beam position switching to the 9006. Both are single-filament halogen bulbs with replaceable capsules rather than sealed beam units.
• The 9005 operates at 12V and 65W with a P20d base, while the 9006 operates at 12V and 55W with a P22d base. Although the two bulbs are physically similar, their base types differ, and they are not interchangeable between the high and low beam positions.
• All bulb types listed across these specifications conform to ANSI standards applicable in both the United States and Canada.