Peterbilt 270 Headlight Bulb Size

Additional Notes

• The Peterbilt 270 (2001-2003) accommodates three distinct headlamp system configurations: a two-rectangular-headlamp setup, a four-rectangular-headlamp setup, and a halogen capsule headlamp setup. Each configuration requires different bulb types for both high and low beam positions, making headlamp system identification a necessary step before sourcing replacement units.
• The H6054 is a 5x7-inch rectangular sealed beam unit operating at 12V and conforming to ANSI standards applicable in the US and Canada. It serves as both the high beam and low beam bulb in the two-rectangular-headlamp configuration across all three model years, meaning a single unit type handles both functions in that setup.
• The 9004 is a dual-filament halogen bulb rated at 12V with a 65W high beam filament and a 45W low beam filament, fitted with a P29t base. Its dual-filament design allows one bulb to serve both high and low beam functions within the halogen capsule headlamp configuration. It conforms to ANSI standards for the US and Canada.
• Sealed beam units such as the H6054, H4651, H4656, and H4652 are not serviceable at the bulb level. When a sealed beam unit fails, the entire assembly requires replacement rather than an internal component.
• In the four-rectangular-headlamp configuration, the high beam and low beam positions use separate 4x6-inch sealed beam units. The H4651 is specified for the high beam position, while the low beam position uses the H4656 for 2002-2003 and the H4652 for 2001.
• The H4652 is described as a variant of the H4651. Despite their shared physical format as 4x6-inch rectangular sealed beam units, they carry distinct ANSI designations and are not listed interchangeably within the specifications. The H4652 appears exclusively in the 2001 low beam position under the four-rectangular-headlamp configuration.