Peterbilt 224 Headlight Bulb Size

Additional Notes

• The Peterbilt 224 (1987-1994) was offered with four distinct headlamp configurations: two rectangular headlamps, four rectangular headlamps, four round headlamps, and halogen capsule headlamps. Each configuration requires a different bulb type for both high and low beam positions, and the correct type is determined strictly by the physical headlamp assembly installed on the vehicle.
• The H6054 is a 5x7-inch rectangular sealed beam unit operating at 12V. It serves as both the high beam and low beam bulb in the two-rectangular-headlamp configuration across all model years covered in the specifications, meaning a single unit type handles both functions in that setup.
• The 9004 is a dual-filament halogen bulb with a P29t base, rated at 12V and 65W for high beam and 45W for low beam. Because both filaments are housed within one capsule, the 9004 also serves both high and low beam functions in the halogen capsule headlamp configuration, across all covered model years.
• All sealed beam units listed in the specifications, including the H6054, H4651, H4656, H4652, H5001, and H5006, are replaced as complete assemblies rather than as individual bulbs. The lens, reflector, and filament are fused into a single unit, so a failed filament requires full unit replacement.
• The four-rectangular-headlamp configuration uses separate bulb types for high and low beam positions. The H4651 is specified for high beam, while the low beam position uses either the H4656 or H4652 depending on the model year. All three are 4x6-inch rectangular sealed beam units operating at 12V, though they are not interchangeable with one another.
• The H4652 is described as a variant of the H4651 and shares the same 4x6-inch rectangular sealed beam format at 12V. Despite their physical similarity, the specifications treat them as distinct part numbers assigned to different beam positions and model years, which means substituting one for the other is not supported by the listed fitment data.
• The four-round-headlamp configuration uses the H5001 for high beam and the H5006 for low beam across all covered model years. The H5001 is a 4-inch square sealed beam unit, while the H5006 is a 5.75-inch round sealed beam unit, both at 12V. The physical size difference between these two units means they are not interchangeable between positions.
• All bulb types listed in the specifications conform to ANSI standards applicable in both the United States and Canada, and all operate on 12V electrical systems. The halogen capsule configuration is the only one in the specifications that uses a replaceable bulb rather than a sealed beam assembly.