Peterbilt 367 Headlight Bulb Size

Additional Notes

• The 9003 bulb is a dual-filament halogen type that serves both high and low beam functions within a single housing. On the Peterbilt 367, it appears across both high beam and low beam positions for model years 2010-2015 equipped with halogen capsule headlamps, making it the most frequently specified bulb across the full range of these specifications.
• The 9004 bulb is also a dual-filament halogen type, handling both high and low beam output from one unit. It is specified for 2008-2009 models fitted with halogen capsule headlamps, covering both beam positions simultaneously in that configuration.
• The H4651 and H4656 are sealed beam rectangular lamp types that differ by function: H4651 handles high beam output and H4656 handles low beam output. On the 367, H4651 is listed for high beam and H4656 for low beam across 2008-2015 model years in sealed beam configurations, and they are not interchangeable with each other despite their similar designations.
• The H6054 is a large rectangular sealed beam unit rated for both high and low beam use. It is specified for 2008-2009 models equipped with a two-rectangular-headlamp arrangement, where a single lamp per side covers both functions rather than using separate bulbs for each beam.
• The 9005 is a single-filament halogen bulb dedicated solely to high beam output. It is specified for the Peterbilt 367 high beam position in 2016-2017, replacing the dual-filament 9003 used in earlier halogen capsule configurations, which means a separate bulb type handles low beam in those years.
• The H11 is a single-filament halogen bulb used exclusively for low beam output. It is listed for the low beam position in 2016-2017, pairing with the 9005 high beam bulb in those years. The H11 uses a PGJ19-2 base and is not physically compatible with sockets designed for 9003 or 9004 bulbs.
• The 2008-2009 model years carry the most complex fitment structure in these specifications, with up to three distinct bulb options per beam position depending on whether the vehicle has a two-rectangular-headlamp setup, a four-rectangular-headlamp setup, or a halogen capsule headlamp system. Selecting the wrong bulb type for the installed headlamp housing would result in an incompatible fit.
• The transition from sealed beam to halogen capsule headlamp systems on the 367 represents a fundamental difference in headlamp construction. Sealed beam units integrate the lens, reflector, and filament into one sealed assembly, while halogen capsule systems use a replaceable bulb within a separate reflector housing. These two systems require entirely different bulb types and are not cross-compatible.
• For 2010-2015 models with halogen capsule headlamps, the 9003 bulb fills both the high beam and low beam positions using the same part number. This means both positions draw from the same bulb specification, though each housing is a physically separate unit dedicated to its respective beam function.
• The four-rectangular-headlamp configuration listed for 2008-2009 uses H4651 for high beam and H4656 for low beam, splitting the two functions across separate sealed beam units. This differs from the two-rectangular-headlamp setup in those same years, which uses the H6054 for both functions, so headlamp count on the vehicle directly determines which bulb specification applies.