The Powr-Pak 4×4
The exact date of the very first NAPCO 4×4 Powr-Pak conversion kit is not well known, and it is a point of endless debate in various forums.
There is agreement that NAPCO reached an accord with GM in 1956 to supply the Powr-Pak conversion kits
The nifty, easy-to-install system could be bolted up on the factory assembly line. GMC would be the first truck line to use the 1,410-pound kit.
The system would be used until 1960
Then GM changed the front axle design so that it was incompatible with the NAPCO system.
These NAPCO trucks would quickly earn the name “Mountain Goat”
This was due to their ability to traverse rough terrain
Trucks off the line could barely slog through a muddy field.
That all changed with the NAPCO 4×4 system installed.
Now ranchers, farmers, and sportsmen had a vehicle that could handle the task.
NAPCO ads featuring the system proclaimed proudly that you could “now have a standard Chevrolet four-wheel-drive pickup featuring the traction power of a tank, or, at the flip of a finger, a smoother-riding, high-speed, over-the-road truck.
Aptly named the Mountain Goat, this full-sized pickup will literally leap up mountains, as well as carry you through deep mud, sand, or snow.”
Initially, the system could be ordered only on a Chevrolet truck with the 235-ci, 6-cylinder engine
GMC owners could have it installed on V8 configurations.
If you were late to the party, a dealer could install the system and convert your formerly two-wheel-drive truck into a four-wheel-drive ground pounder.
NAPCO’s Powr-Pak system was not only easy for a dealer to install, but easy to service as well.
Their two-speed 4×4 conversions were composed of 85% GM parts.
An up-and-down market
Over the years, the truck market has been on a slow, tedious climb.
Super-nice trucks started to flow into the auctions and found remarkable money — by truck standards, at least.
As the market grabbed hold and gained traction, more and more formerly gunshot trucks started to get pulled out of barns and fields as restorers hunted them down. The better the body, the more value the truck had.
Recently, however, the truck market has once again sparked with collectors
Values have begun to climb for extremely nice restorations. Our subject truck is a shiny example of that.
An extraordinarily rare Cameo
Most NAPCO 4×4 systems are usually found on a more muscular truck, such as a Suburban or 3200 Series Apache.
Conversions were done to transform a work truck into a better work truck, one that could haul parts, a load of fill or a bed full of manure across a muddy field.
Cameos were stylish and marketed to an elite crowd. A gentleman’s truck for sure.
This truck as equipped likely listed somewhere in the neighborhood of $3,521 back in 1958, which was not cheap.
NAPCO (Northwestern Auto Parts Company) was a four-wheel drive automobile parts manufacturing company founded in 1918.
It was based in Minneapolis, Minnesota
During World War II, NAPCO helped the war effort by producing:
- Specialized mechanical parts
- Assemblies that were tested in war conditions.
As early as 1942 NAPCO began building four-wheel drive assemblies to be fitted to:
- Chevrolet and Studebaker vehicles
NAPCO is primarily associated with GMC and Chevrolet pickups.
From 1942 to 1956 4×4 GMC and Chevrolet trucks could be ordered by the government and civilians with a NAPCO Power-Pak kit and the kit could be installed later.
The retail price of Napco Power-Pak was $995.
This option raised the price on a new two-wheel drive truck from $1,548.96 to $2,796.96.
The kit was shipped in a crate measuring 80″x30″x26″ weighing 1,410 pounds.
In a matter of 3 hours with as little as 4 holes drilled in existing chassis a truck would be converted into a “Mountain Goat”
It was a “full sized truck that will climb steep inclines with ease”. One feature was the “shift on the fly” rubber mounted transfer case with a dual-range option.
There were companies that installed these upgrades for the previously mentioned manufacturers.
Besides the four-wheel drive units NAPCO also provided:
- Auxiliary transmissions
- Tandem drive axles
- Hydrovac systems
- Dump truck bodies.
A 1958 Chevrolet Apache pickup truck with the NAPCO Power-Pak conversion
From 1956 to 1959 the NAPCO Power-Pak option could be ordered directly from GM (an official RPO 690 was assigned in 1957).
It could be factory installed on trucks with very few modifications to the original chassis.
The 1955 4×4 NAPCO GMC or Chevrolet was a $1250.00 to $1550.00 optional add on.
The 1957 Chevrolet and GMC 3100 4×4 price was a bargain at $2549.00
In 1960 NAPCO and GM parted ways when GM redesigned the front suspension on their 1960 pickup line so that it wasn’t easily compatible with the existing Power-Pak kits.
Prior to 1955 NAPCO Power-Pak conversions were done on 3/4 and one ton GMC and Chevrolet chassis.
The Pre-1955?1?2 ton chassis used an incompatible “torque tube” drive.
In the fall of 1954 GMC and Chevrolet changed the 1955?1?2 ton pickup and Suburban models to the compatible Hotchkiss drive.
Today these trucks are still considered to be very versatile and durable 60 years later and are considered to be collectible by NAPCO enthusiasts.
Early factory 4×4 pickup manufacturers and early 4×4 conversion kit manufacturers include:
- Marmon-Herrington in Indianapolis.
- Willys Overland along with Ford built the Willys MB Jeep working from designs by the American Bantam Car Company
- After W.W.II Willys-Overland built the CJ series, and Willys Wagons among other early 4×4 vehicles.