If One Is Good, Two Must Be Better: The Tandem Tractor Era

Editor’s note: This article was written by my grandfather several years ago before he passed away. I recently found it and made a few modifications to his original manuscript. He left a note on it stating he hoped to have it published.

Today’s high horsepower, 4-wheel drive, track units, and front-wheel assist have replaced all but memories of the tandem tractor era. This new wave of power came late in the 1950s and early 1960s. My farm life had been interrupted by a two-year stay in the U.S. Army, one year of which I spent in Korea as a tank mechanic and motor sergeant. I came back to find the girl of my dreams, and after working at a couple mechanic jobs, returned to the farm with my new wife.

Like many other farm boys, I had my first taste of big horsepower as I worked with and learned more about large horsepower in tanks and other military equipment and wondered why tractor makers had not also seen this wave of power increase. Many components needed in these farm tractors were just being developed, like heavy-duty electrical systems and hydraulic power, along with power steering and even larger wheels and tires to go with the power train. Some were trying to make and sell front-wheel assist, and a local company went bankrupt as they proceeded to make and sell an aftermarket version.

The Steiger brothers started making successful 4-wheel drives. I remember touring the John Deere tractor factory. During a question period, the engineers were asked about front-wheel assist. One of the engineers spoke up and said the only benefit to the tractor was the added weight. I suspect he was later transferred to the lawn and garden division.

Some re-powering was done with a degree of success and there were many under-engineered failures as well. Farm innovators like myself had two tractors that could work together but needed a second person to operate. When I heard of this new idea of a tandem tractor, I followed up on it. And after seeing one in action, I decided to make my own unit using two tractors I had.

The Birth of ‘Big Bad John’

In the 1960s, Jimmy Dean had the hit song “Big Bad John,” and I had this on my mind when I named my first tandem unit, consisting of a John Deere 730 and a 720 diesel. This was not the first unit ever built, but it was the first in our area.

I also built a two-plow hitch that worked well but left no chance at all to back up. I soon ordered a new 6-bottom John Deere plow that also did not like reverse. For my first unit, I found a used 6-inch I-beam for the main frame, and later learned I could get the same strength from a 4-inch H-beam, which gave 2 more inches of ground clearance.

It seemed like about every year someone wanted my hitch, and I made several units with a lot of advice from others. My goal was to make it as safe as possible, place no additional stress on either tractor, and, of course, keep the cost low. The University of Illinois had enough interest in tandem tractors to print a booklet on them.

Tandem tractors were a full-time job to operate as they would jackknife easily when turning if the rear unit speed was not reduced. Slippery conditions called for fast reactions as well. I don’t know of any serious accidents, but the potential was always there. I used ½-inch tubes to make control rods; some people used hydraulic controls. I ran out of hydraulics on my tractors and liked the feel of the hand controls.

On the John Deere hand clutch units, I had to clutch the front one with my foot while engaging the back one with a hand control. The clutch had a D-handle and the throttle had a knob for easy identification without looking back. This worked so well that we made a second unit for use in our farming partnership at that time. With two other single units, we were turning 19 furrows at each pass and the fields shrank rapidly.

Putting Them to the Test

Being close to to Peoria, Illinois, and Caterpillar Tractor Company, we attracted the attention of one of their engineers who built a unit of his own design. This was a great design with no wasted front-wheel weight on the ground, but it was far from simple and a real job to put together. Plus, it tied the unit together until the plowing season was done.

The real test came when the Heart of Illinois Fair opened up a pulling class that tandems could compete in. In the first pull, we tied with the articulated unit, but after more weight was added to the skid, my unit won very easily due to weight distribution others could not match due to design.

This was a big event and a first for this type of competition. Pull-down from the skid caused the other unit to require most of the power from the rear tractor while the front tractor spun out. This was a serious loss for the other articulated unit, and I don’t believe any more were made.

We saw unit matches of all kinds come out. Most made use of an older tractor on the rear and a newer tractor up front. We used different combinations with a John Deere 80 up front on one unit, and later, the New Generation tractors — a John Deere 4010 and 3010 combination. One year, I spent the entire fall season plowing while my farming partners did the harvest. After our partnership broke up, I did some custom plowing after finishing my own. I always got the hard plowing jobs, so I charged $4 an acre plus fuel.

Tandem Tradition Lives On

We have one tandem unit on our farm which is made up of two Case 500 diesel tractors with a hitch similar to the one I made. (Editor’s note: We still have this unit and use it occasionally). This would have made a good combination for that era. To those of us who like to hear a good engine doing its job, the tandems only doubled that pleasure and hearing two 2-cylinder John Deeres working together was truly unique.

Side-by-side doubles also deserve a mention, as they are a real engineering wonder. The unit that takes first place in my rearview mirror was sold to me by an Allis-Chalmers heavy equipment salesman.

He was involved with a huge sale to a Canadian contractor who ordered two of the largest Allis crawlers made without the left track assembly on one and the right track assembly on the other one. These would be put together at the construction site as twins and steered mainly with the engine throttles. If m memory is correct, these were HD21s with the new 6-110 Detroit engines.

When the contractor was asked what his plans were for the tractors when he was done with them, he replied, they would run until they died and then rust out in the northern woods of Canada. Unlike the tandem tractors that remained standard in power and power train, new weak points must have surely shown up in units like these as power doubled to some important parts.