NAPCO 4x4history
There are stories of GM trucks being converted as early as late 1949, but the earliest documented truck known of is a 1951 Chevy 3/4 ton owned by Butch Gehrig of Odell, Oregon.
Until October 28th of 1954, when Chevrolet introduced the 1955 1st Series, all the conversions were done on 3/4 ton and larger trucks.
The 1954 and earlier Advance Design 1/2 ton models were not suitable for a NAPCO conversion due to the enclosed drive shaft design.
GMC and Chevrolet conversions were by far the most popular, though conversions were available for Ford, Studebaker and other manufacturers.
NAPCO reached an agreement with both GMC and Chevrolet to supply them with the Powr-Pak conversion kits, and GMC began to produce 4x4 trucks on the factory assembly line (using NAPCO components) starting in 1956, with Chevrolet following suite in 1957.
By the end of 1957 both GMC and Chevrolet trucks could be ordered from the factory with the NAPCO Powr-Pak conversion.
The first 'All GM' factory 4x4's were introduced in 1960 when both Chevrolet and GMC went to a totally new chassis.
NAPCO and its Powr-Pak conversion were left out of the equation due to the introduction of GM's completely redesigned truck line featuring independent front suspension on the two wheel drive trucks and a 4-wheel drive specific chassis on the 4-wheel drive trucks. This was the beginning of the end for the 4x4 conversion element of NAPCO.
Though they did produce conversion kits for a few more years, their main business shifted to the heavier trucks, 1-1/2 ton and larger.
After the huge loss of the contracts with GMC and Chevrolet to supply conversion packages, NAPCO sold the rights to the Powr-Pak package to the DANA Corporation All documentation, archives, information and parts were transferred to DANA at that time.
During this evolution, the association of the NAPCO name with 4x4's ceased to exist. The NAPCO 4x4 had vanished, just as it's associated history, archives and NOS parts supplies were absorbed into DANA
