A Brief History of Deere’s Self Propelled Combines

One of Deere’s earliest self propelled prototypes was a No. 9 combine, which was pushed through the field by a model “A” tractor.

The No. 14 combine was an attempt to develop a self propelled combine from the No. 12 pull type. An attempt to keep the tractor narrower than the six foot head by mounting the Hercules four cylinder engine and grain tank on top must have resulted in a rather high center of gravity.

Deere engineers decided to overcome the top-heavy problem by giving the machine a wider head and mounting the grain tank on the right and the mechanicals on the right.

This combine would become known as the No. 44 and engineers apparently thought enough of its potential to develop a track version.

The No. 44 eventually got to a ready-for-production machine, but apparently by this time it was deemed that such a small combine would not be a sales success.

Early development on what would become Deere’s first production self propelled, the No. 55, was based on the threshing unit from the No. 9 pull type. Initially the engine was mounted behind the operator’s platform at near ground level, similar to the International Harvester units of the era. However, uneven weight distribution and a complicated drive train caused the engineers to look for other solutions. One prototype from 1944 had the engine mounted beside the operator in a longitudinal manner.

This photo, from March of 1945, shows a combine with draper platform that is getting closer to its final form.

Here’s a first year production (1947) model 55.


The first No. 55 combines were shipped with 9 by 24 inch tires and had a 30 inch cylinder and 45 bushel grain tank. A six cylinder Hercules QXD-3 engine producing 45 horsepower supplied the power. Early machines did not have individual wheel brakes, but only a transmission brake. For 1948, standard tire size was raised to 13 by 26 inch.

The 55R had extra clearance and flotation for rice field conditions. Other enhancements gave it a weight of over 1,000 pounds more than the regular 55.

The tracks for the 55RC were developed by Deere and Caterpillar. A rubber track designed by BF Goodrich was considered.