Branded by International Harvester as McCormick-Deering products, with the same styling and red paint as the Farmall line, the W series had fixed wheel widths, lower height and wide front axles.

In contrast to the letter series row-crop tractors, which were intended to straddle one or more rows in a field with high clearances and adjustable axles, the W tractors had fixed wheel widths and a generally lower profile with smaller rear wheels and wide front axles, since they were meant for plowing, orchards, wheatfields and other applications that did not require the row-crop features.

[1] The McCormick-Deering W-4 was based on the Farmall H and used the same International Harvester C152 152-cubic-inch (2,490-cubic-centimetre) displacement gasoline engine, with options for kerosene and distillate fuels.

A five-speed sliding-gear transmission was standard, with fifth gear disabled on tractors that were delivered with steel wheels.

Overall weight for single rear wheel tractors was about 3,800 pounds (1,700 kg).

A McCormick-Deering O-4 was intended for vineyards and orchards, and had fenders and fairings designed to avoid snags on branches, with the exhaust routed underneath instead of overhead.

The remainder of the W-6 drivetrain was similar to the W-4's, but the tractor was heavier at 4,800 pounds (2,200 kg).

[8] OS-6 and ODS-6 models omitted the sheet metal guards, but kept the rearranged exhausts.

[9] The McCormick-Deering W-9 departed from the letter series parallel, using much more powerful engines from International Harvester's crawler tractors, and heavier drivetrains.

Industrial tractors were the International I-9 and ID-9, and a special steel-wheeled rice field variant was the WR-9 and WDR-9.