The tractor was equipped with a two-cylinder side-by-side 17-horsepower (13 kW) engine, of 149-cubic-inch (2,440 cc) displacement.

The BR standard tread tractor was introduced in 1936 as well, with fixed axle widths and a lower profile, for farming uses that did not involve row-crop cultivation.

For compatibility with Model A cultivation accessories, the frame was extended in 1937, referred to as "long-frame" Bs.

High-crop versions of all subtypes were offered beginning the same year, with various combinations of letter designations.

Further updates in 1947 mirrored those of the A, with improvements to operator comfort and a larger engine that produced 15% more power.

[4][2][3] All Bs were manufactured at the John Deere factory in Waterloo, Iowa, where 40,057 were built, with a sale price of about $1,900.

Power output was increased 20%, with a new two-cylinder engine, to the point that the 520 could work three plows.