The term “Highboy” has been used to refer to the 1967-1977.5 Ford F-250 4X4, although ‘Highboy’ wasn’t actually a Ford term. The early 4X4 pickups were conversions of a 2WD chassis. It was simpler and cheaper to utilize the original 2WD transmission than to design an adapter to marry them. This meant that the transfer case (either Dana 24, NP203, or NP205) was connected to the transmission with a short driveshaft (also referred to as being a divorced transfer case) rather than being married to the back of the transmission like they are today.
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