Not long after Holt’s “Caterpillar” tracked tractors hit the market, the Bullock “Creeping Grip” came on the scene for a brief run.
A prototype of a full crawler from the Bullock Tractor Company, made in 1913, can be seen in the video above as volunteers at the Historical Construction Equipment Association’s 39th annual International Convention in September got the unique tractor’s rare Heer opposed-piston engine running.
The 100-year journey of the one-of-a-kind Creeping Grip prototype to the Historical Construction Equipment Museum in Bowling Green, Ohio, can be traced to Henry Bullock, a wealthy businessman in Chicago.
In 1913, Bullock acquired the bankrupt Western Implement & Motor Company of Davenport, Iowa, along with its patents for the Creeping Grip tractors.
Bullock wanted to produce a “practical crawler tractor” for farming and construction, according to the HCEA. The 1913 prototype was the first unit of his desired model produced by the newly formed Bullock Tractor Company in Chicago.
The tractor runs on a 2-cylinder Heer opposed-piston engine. The prototype is the only known Bullock that runs on the Heer engine, in which the pistons work in opposite motion, according to the HCEA. Bullock tractors after that got 4-cylinder upright engines.
The prototype was never sold. Instead, Bullock kept it for his ranch in the Upper Peninsula of Michigan for farming and logging. In 1933, the ranch closed, and Bullock gave the tractor to the ranch manager who used it to power a sawmill in Seney, Michigan.
Years later, a collector in Michigan bought the Creeping Grip prototype. After that, it was sold at auction in 1997 to Glenn Higgins of Rosebush, Michigan.
Higgins donated the tractor in 2013 to the HCEA Museum, where it remains today and makes occasional appearances at the association’s shows.
Creeping Grip Short-Lived
As for the Creeping Grip line of tractors, Bullock released the Creeping Grip 12-20 to the market in 1916. The fully tracked tractor replaced the half-track, half-wheeled Baby Creeper model, according to a Farm Collector article.
The Creeping Grip name was also used for the company's Creeping Grip Senior tractor, which had two wheels up front and tracks in back, and the Creeping Grip Junior, which had one wheel up front and rear tracks, according to a 1914 Bullock Tractor catalog.
The full-crawler Creeping Grip 12-20 ran on a 4-cylinder Waukesha engine, “had a large, round tubular radiator at the front, the engine amidships and a bench seat at the rear,” the Farm Collector article says.
“The tractor cost $1,250 in 1916 …, had one speed forward and one reverse, weighed about 7,200 pounds, and there was no canopy or hood to protect the machinery.”
In 1920, Bullock Tractor merged with Franklin Tractor Co. of Greenville, Ohio, to form the Franklin-Bullock Tractor Co., which folded in 1922.
Heer Engines Also Short-Lived
The Heer engine the HCEA's Creeping Grip prototype runs on was also short-lived.
Heer Engine Co. was formed by Chris Heer around 1910 in Portsmouth, Ohio, producing 2-cylinder opposed-piston engines and tractors.
The company was reorganized in 1915 as Reliable Tractor and Engine Co. and folded in 1921.
Photos of the 1913 Bullock Creeping Grip
The following photos were take by Equipment World at the 2025 HCEA International Convention and Old Equipment Exposition:
Equipment World
For more coverage of vintage construction equipment from the 2025 HCEA show, check out:
- Watch Antique Tractors from Holt, Best, Caterpillar at HCEA Show 2025
- Rare Survivor! – 1930 Cat Thirty with All-Original Parts Still Going Strong
- “The Scoopmobile!” — Dr. Seuss-Like Wheel Loader an Odd, Rare Sight (Video)
