Doodlebug AdFarmers have often been reluctant to adopt new technology.  Few have had the luxury of time and money to experiment with new gadgets that may or may not pay off. However, once a labor-saving device has shown its worth, farmers have eagerly sought to adopt anything that promised to make their work easier and more profitable. This has been especially true with the farm tractor. During the early 1900's, the first tractors were large and expensive--far beyond the needs and resources of most farmers. Once the need for huge tractors to plow the prairies was over, manufacturers developed smaller tractors to help with other tasks on the farm. Unfortunately, costs remained high and only those on large farms could justify the expense. The price of a tractor with a good reputation, such as Titan 10/20 or a Waterloo Boy Model N, was approximately $1,000.

On the other hand, the Model T Ford was priced so that even someone on a modest farm could afford one, and they rapidly became a common sight on the landscape. Introduced in 1908, the Model T was produced until 1941. At peak production, two million Model T's rolled off the assembly line annually. An initial cost of $850 was reduced to $440 in 1915 and $260 in 1920. The "Tin Lizzie" sold for half the price or less of a good tractor.

With an abundance of used Fords available, resourceful farmers turned their talents to converting them for use as tractors. Two types were common: tractors employing factory conversion kits and tractors assembled from used automobile and truck parts acquired locally.

By 1920, over forty firms such as Sears and Montgomery Wards offered after-market tractor conversion kits. A typical kit included a subframe with reduction gears and large rear wheels to replace the original differential and wheels. Some kits utilized  final drives that were totally gear driven; others incorporated chain drives. The resulting tractors were adequate for light tasks such as dragging, hauling and raking, but weren't up to heavier tasks such as plowing. In particular, the Model T's friction-band planetary transmission was too weak for tractor use.  Some companies selling conversion kits claimed that tractors with their kits could be used in the field during the week and then changed back for passenger car use on the weekend. This rarely was satisfactory because it involved too much effort, and, by  the weekend, the tractor was too dirty for more  genteel use.  

Doodlebug4Farmers that couldn't afford a factory conversion kit produced their tractors using whatever vehicles and parts were available locally. Magazines such Popular Mechanics and Mechanics Illustrated provided instructions for building a tractor. Some articles claimed that a workable tractor could be built with a wrench, a hacksaw, a drill press and bits, and some minor welding for an estimated cost of $25 to $50. 

By the late 1920's, manufacturers such as Ford and Chevrolet were producing automobiles with the potential for conversion to tractor use. The Model A Ford, in particular, was readily available and a popular choice. Factory-produced conversion kits were usually less popular than conversions incorporating automobile and truck parts obtained locally--often from salvage yards. A typical conversion involved shortening the frame of the automobile or truck, modifying and discarding body parts, adding a second transmission mated to a truck differential, and constructing a hitch. Some conversions had small truck beds. It was sometimes necessary to replace the radiator with a larger one, as the conversion had a tendency to overheat. The resulting tractor had weaknesses inherent to the original automobile in that it was underpowered, the clutch and transmission weren't sufficiently durable, and the rear of the tractor had to be weighted for traction. A tractor with two transmissions was normally driven in the field with both transmissions in low gear. For use on the road, one transmission was in low gear and the other in second gear. Any other combination resulted in too much speed, considering that the brakes were inadequate, the tractor was difficult to steer, and the large rear wheels were prone to severe vibration.

Doodlebug1Tractor conversions were popular for several reasons. Some farmers couldn't afford a regular tractor or weren't eligible for credit--especially during the Great Depression of the 1920's and 30's. Some had limited acreage and couldn't justify the cost of a regular tractor. During the Second World War, tractors weren't available because manufacturers were involved in producing items to support the war effort.

Tractor conversions have been affectionately called Doodlebugs, Jitterbugs, Puddle Jumpers, Friday Tractors, Field Crawlers, Scrambolas, Handy Henries, etc., depending on time and location. Sometimes these names were only attached to tractors produced locally in their entirety. and tractor conversions based on factory-produced kits were simply called that. A different kind of conversion was the Hoover Wagon used during the Great Depression; this was an automobile pulled by a horse when gasoline wasn't available.  

Tractor conversions have been popular in Sweden from the 1930's on. They have been powered with either gasoline or diesel engines. During the World War II era when there was a shortage of gasoline and diesel fuel, some conversions were outfitted wood gasifiers. Currently, conversions provide transportation for some young people before they are old enough to drive regular trucks and automobiles. These tractors are known as A tractors (arbetstractors) and they are limited by law to maximum speeds of 30 k/h.

Doodlebug2Tractor conversions were common in the United States from the 1910's into the 1950's. Occasionally a tractor conversion is done now to produce a vehicle for recreational purposes. Tractor conversions have been especially popular in New England and the upper New York area, and there have been a number of social clubs based on them. Two clubs active in recent years include the Doodlebug Club of Canterbury, New Hampshire, and the Doodlebug Club of Franklin, New York.

Websites of possible interest include and

A large number of photos of doodlebugs and tractor conversions are available at the following sites: and At each site, conduct two searches: one under doodlebug tractors and another under model a ford tractor conversion kits.