The Kenworth K220 high beam headlight uses an H4651 bulb size, while low beam headlights require either H4656 or H4652 bulb sizes. The replacement chart covers vehicle production years spanning 1988 to 1994.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The H4651 is the sole high beam sealed beam unit specified for the Kenworth K220 across all listed model years, 1988-1994, with no variation across that span.
The H4651, H4652, and H4656 are all ANSI-standardized 4x6-inch rectangular sealed beam units rated at 12V. In sealed beam construction, the lens, reflector, and filament form a single fused assembly, meaning the entire unit is replaced rather than an internal bulb.
The H4652 is documented as a variant of the H4651. Both share the same 4x6-inch rectangular sealed beam form factor and 12V rating, though they carry distinct ANSI designations and serve different lighting functions.
The low beam position on the Kenworth K220 alternates between two different sealed beam types depending on the model year. The H4656 is specified for 1989, 1991, and 1994, while the H4652 is specified for 1988, 1990, and 1992.
Because the H4652 and H4656 are distinct ANSI designations assigned to different model years in the low beam position, substituting one for the other without confirming the correct year-specific specification would constitute a fitment mismatch.
All three sealed beam types, H4651, H4652, and H4656, conform to ANSI standards recognized in both the United States and Canada, placing them within a regulated dimensional and photometric framework.