One word describes those early Prairie tractors: BIG.
Avery 40-80 tractor.



They were huge machines designed and sold for one purpose, to break the centuries-old sod of the Midwest. These gas-powered behemoths were sold to replace steam traction engines.
Most of these tractors were built in the early 1900s, primarily in the ‘teens. There were many manufacturers: Advance-Rumely, Aultman & Taylor, Avery, Case, Emerson Brantingham’s Big 4, Gaar-Scott, Hart-Parr, Huber, IHC Mogul and Titan, Kinnard-Haines Flour City, Minneapolis Threshing Co., Minneapolis Twin City, and the Wallis Bear, to name a few.
They were heavy. Most tipped the scales at six tons or more. They were tall. Rear wheels on most were at least 8 feet high. All came on steel wheels equipped with steel lugs of some kind. They were powerful. Most were 30-60s, 35-70s or 40-80s.
Although they used a lot of fuel, in the Plains states, kerosene, distillate and gasoline were more plentiful than the coal or wood required to fire steam traction engines. They had large cooling system reservoirs, but they needed less water than did a steam engine. Some, such as the Hart-Parr and Rumely, used motor oil for coolant.
These tractors could pull an 8-bottom platform plow in tough soils. But occasionally, even with the weight and power, they would need more traction. Aultman & Taylor helped solve that problem. The company provided what is called a “mud lug.” It went between the two existing chevron lugs. The mud lug was about 3 inches deep to provide extra traction. Dan Ehlerding, Jamestown, Ohio, has a complete set of mud lugs for his 30-60 Aultman & Taylor.
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The rear fenders of some Aultman & Taylor tractors slid up to allow mud lugs to be mounted. |
Aultman & Taylor
On Aultman & Taylor tractors equipped to use mud lugs, each rear fender had a sliding panel (or door). When raised,  the rear wheel was exposed. That made it much easier for the operator to add the mud lug. He simply raised the door and bolted the mud lug in place. Then he moved the tractor forward far enough to expose the next position for mounting a mud lug. He repeated the process until all the lugs had been installed on both rear wheels.
Voilà . Now the tractor could get a better grip in wet land or loose ground to pull a heavy load without slippage. Dan says the Aultman & Taylor was well built, reliable, durable and long-lasting. Many are still around: That’s why you see more of them than any other prairie tractor at shows.
After the big push to break prairie sod, most of these big tractors were used in road construction. The company was bought out by Advance-Rumely in 1924. In 1931, Allis-Chalmers bought out Rumely, primarily to acquire the company’s sales outlets and the famous Aultman & Taylor separator. But that’s another story.