An Alpine CD head unit and 600-watt amp produce ample vibes through the two 6-1/2-inch diameter Alpine speakers. Ron Garrod Upholstery is responsible for the flawless retro red/white leather tuck 'n' roll bench seat and matching door and kick panels. The simple interior is timeless. An ididit tilt steering column is capped with a white leather-wrapped LeCarra steering wheel. Whiteface Classic Instruments fill the six-gauge cluster on the dash.
It seems Chris and John's '55 GMC NAPCO is an award magnet wherever it's displayed. The opportunity to feature this rare old Detroit iron and unique Minneapolis engineered drivetrain is a compliment to Truckin' magazine.
Napco HistoryAt first glance this viper red '55 GMC pickup appears to be an aftermarket, lifted 4x4. But if you look closer you will notice the NAPCO badging on the fender. What is NAPCO? It stands for Northwestern Auto Parts Company. During the mid-'50s NAPCO started producing their Powr-Pak 4x4 conversion kits for OEM GMC and Chevrolet. Later, the Powr-Pak 4x4 kits were available for Ford and Studebaker trucks.
During the WWII years many automotive part companies focused their attention on projects commissioned by the United States government. During this time of war the parts and assemblies were tested on the largest proving ground on the planet, under extreme conditions. After the war, government priorities changed and NAPCO redirected its vast engineering and manufacturing experience to produce goods for private industry, which included the production of the famous NAPCO Powr-Pak 4x4 conversion.
There is some mention that NAPCO started producing 4x4 conversions for GM trucks as early as 1949. But it was not until October 28, 1954, that Chevrolet introduced the '55 1st Series. All of the NAPCO conversions were done on 3/4-ton and larger trucks. GMC and Chevrolet were the most popular conversions. (Later the NAPCO conversions were available for Ford, Studebaker, and other manufacturers.)
During 1955 NAPCO was very busy pushing its proven 4x4 conversion kits on truck upfitters and some of their GMC dealers across the country. That's why this '55 GMC is rare. Upfitters were companies that installed upgrades and accessories like winches, auxiliary transmissions, tandem drive axles, dump beds, and hydrovac systems on stock factory trucks. These NAPCO-enhanced vehicles were branded with the name "Mountain Goat" expressing their climbing abilities.
The NAPCO Powr-Pak 4x4 conversion kits were not available for GMC until 1956, then followed with Chevrolet in '57. By the end of 1957, both GMC and Chevrolet trucks could be ordered from the factory with the NAPCO Powr-Pak conversion. The two offered identical systems, other than the availability of a V-8 and an automatic transmission on the GMC trucks. The Chevrolet could only be ordered with the 235ci six-cylinder and a four-speed manual transmission.
The first "All GM" factory 4x4s 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 four-wheel-drive specific chassis on the four-wheel-drive trucks. This was the beginning of the end for the 4x4 Powr-Pak conversion element of NAPCO. NAPCO did produce conversion kits for a few more years, but the main business shifted to the heavier trucks (1-1/2 ton and larger).
After a major 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 in 1961. It seems that since NAPCO was bought by DANA Corp it was pulled into its black hole during the merger or buyout of SPICER. Who knows?