Gibson’s Horsepower Legacy

The cessation of World War II in 1945 found industrialists like Wilber Gibson looking for new markets for their manufactured goods. Gibson had been experimenting with tractors at his father’s plant in Seattle. He sensed that service-men returning from the war and settling down in homes and small farms needed horsepower for tending to chores.

So in 1945, Gibson took his experiments to Longmont, Colorado, to capitalize on that area’s source of nonunion workers and set up shop to produce a line of affordable garden tractors. His approach to manufacturing was to pair up a widely available engine, the 6 hp. Wisconsin Industrial model AEN single-cylinder power plant, with a car transmission and differential obtained from General Motors. Thus was created the first Gibson tractor, the model A, in 1946.

Put-Together Tractors

Garden tractors were by no means spawned by the emerging era of the consumer society, which came to full force and vigor after the war. What was new was the sudden entry of dozens of new firms, such as Gibson Manufacturing, into an expanding market.

Often their creations were put-together affairs fashioned from existing engines, transmissions, differentials, and castings. Such was certainly the case with the Gibson A; it ran with Wisconsin engines and various car transmissions and differentials. The end result was a garden tractor that was overbuilt from parts designed for harder service, though often these parts were used components that had been refurbished.

Tiller Steering

To further keep its retail cost down, Gibson made use of simplistic tiller steering employed by using a lever on the right side of the operator. Yet, the Gibson model A did offer standard amenities such as a height-adjustable front blade and rear hitch raised and lowered by separate levers.

The sale of 500 model A’s encouraged Gibson to expand his efforts in 1947 with the introduction of the model D. This tractor continued to be powered by that Wisconsin AEN engine, but some versions of the tractor came with a single-cylinder, 9 hp. Wisconsin AHH engine.

The D also offered such features as adjustable rear wheels (33 to 54 1⁄4 inch spread) working off a three-speed transmission. Again, the adjustable front blade and hitch were standard features. Optional equipment included a starter generator and fenders.

Implements Added

At this same time, Gibson was selling an impressive line of equipment for his tractors, which included a plow, row cultivator, disk, snowplow, angled dozer blade, spring-tooth harrow, and sickle-bar mower.

Success with the model D spawned a series of tractor variations, which included the stylized model SD that came adorned with a hood, grille, and fenders but kept the tiller steering and Wisconsin AEH 6-hp. engine.

Then came the model Super D still running with that 6 hp. Wisconsin but featuring a steering wheel and gearbox. This tractor was stylized with a hood, grille, and fenders. At the same time, Gibson expanded the D series with the Super D2, which was powered by a two-cylinder, 12-hp. Wisconsin mode lTF engine.

A glimpse at the future of Gibson tractors was seen in the 1947 introduction of the E series of tractors. This included the E (tricycle front), EW (tricycle with rear-wheel adjustment), EF (wide front with an adjustable front axle), and EWF (with a wide tread stance of 84 inches to straddle two corn rows). All of these tractors continued to be powered by Wisconsin model TF two-cylinder engines.

Modernized Gibsons

The model E’s were the first fully modern tractor from Gibson sold with a rear hydraulic lift, PTO shafts on a transfer case (in front of the transmission), and an electrical system. Early E’s had a pedestal supporting the rear of the hood and gas tank, but this was replaced on later versions with a sheet metal and then a cast-iron dashboard.

All told, some 50,000 to 60,000 of the model A, D, and E series would sell in North America and overseas.

Encouraged by this success, Gibson was inspired to enter the full-size tractor market in 1948 with the introduction of the H series of tractors. This line was powered by a Hercules model IXB, four-cylinder engine paired with a three-speed transmission. The H series included the H (tricycle front), HFS (wide front), and HFA (wide front adjustable front axle). Set on an 86-inch wheelbase, the H was evaluated at the Nebraska Tractor Test, where the 4,000-pound tractor turned out a rated 18 1⁄2 drawbar horsepower.

At this same time, Gibson introduced a second full-size tractor in the model I powered by a six-cylinder Hercules model ZXD engine. Mirroring the model H, this tractor came in a series that included the model I (tricycle front axle), IFS (wide front), and IFA (wide front with an adjustable front axle). Set on a 94-inch wheelbase, the 4,000-pound I series operated with 10×38-inch rear tires. When tested at Nebraska, the model I turned out a rated 37 drawbar hp.

Gibson toyed with even larger tractors including the model M (likely a prototype) and model G. The G was mechanically identical to the model I, but it featured a higher driver’s seat, angled steerinwheel, chrome trim, and a hood that could be raised for servicing.

Gibson Line is Sold Off

Facing financial challenges, Gibson sold his firm in 1952 to Helene Curtis Industries. The factory was leased to Western American Industries, which built around 1,000 model D, SD, and Super D tractors.

Wilbur Gibson did go on to produce similar garden tractors in the PowerFlex 10, which continued to be built in several variations (identified with the Harvey PowerFlex name) after Gibson passed away in 1959.