Four-wheel-drive tractors have typically been reserved for “broad-acre” applications such as tillage, scraping, and air seeding, where driving is not limited to the constructs of rows, according to Ryan Shust, marketing manager for Versatile tractors. Shust says, in those applications, horsepower is the main requirement, which 4-wd tractors are designed to deliver. The tractors are built with wider, heavier frames and larger wheels of equal size to transfer up to 600 hp to the ground without spinning or getting stuck.

Row-crop tractors, on the other hand, are designed to provide visibility. Their rigid frame, small front wheels, and narrow chassis allow for tight steering and a clear view of the rows during planting and other row-crop work. But those same features can limit power transfer, says John Bohnker, marketing manager for Case IH row-crop tractors.

“Think of it as a tricycle,” Bohnker explains. “If you load a trike with a 300-hp engine, the wheels are just going to spin, right? It doesn’t have enough weight or footing to transfer the power to the ground. The same thing is true for a tractor. As it grows in horsepower, you have to grow the ability to get that power to the ground by providing enough tire contact and weight to keep the wheels from spinning.”