Mack R Headlight Bulb Size
Mack R headlight bulbs utilize 3 distinct high beam sizes (H6024, H4651, H5001) and 3 distinct low beam sizes (H6024, H4656, H5006) across multiple configurations. The replacement chart covers 1981 through 1991 vehicle production years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
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High Beam Headlight
Years Bulb Size
1981-1991 H6024 (With 2 Round Headlamps) H4651 (With 4 Rectangular Headlamps) H5001 (With 4 Round Headlamps)
Low Beam Headlight
Years Bulb Size
1991 H6024 (With 2 Round Headlamps) H4656 (With 4 Rectangular Headlamps) H5006 (With 4 Round Headlamps) 1983-1990 H6024 (With 2 Round Headlamps) H4652 (With 4 Rectangular Headlamps) H5006 (With 4 Round Headlamps) 1982 H6024 (With 2 Round Headlamps) H4656 (With 4 Rectangular Headlamps) H5006 (With 4 Round Headlamps) 1981 H6024 (With 2 Round Headlamps) H4652 (With 4 Rectangular Headlamps) H5006 (With 4 Round Headlamps)
Bulb Specifications
Description
Bulb Size
ANSI standard (US & Canada). 7-inch round sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V. H6024 ANSI standard (US & Canada). 4x6-inch rectangular sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V. H4651 ANSI standard (US & Canada). 4-inch square sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V. H5001 ANSI standard (US & Canada). 4x6-inch rectangular sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V. H4656 ANSI standard (US & Canada). 5.75-inch round sealed beam unit. Not a replaceable bulb — the entire unit is replaced. 12V. H5006 ANSI standard (US & Canada). 4x6-inch rectangular sealed beam unit, variant of H4651. Not a replaceable bulb — the entire unit is replaced. 12V. H4652