If you thought you were a quasi expert on something as simple as tractor tires, maybe you should think again. There’s more to know than you might think, and it could affect your tractor efficiency and power when you pull into the field this spring.
Engineers at the AgTech Centre in Lethbridge, Alberta, have identified three areas where careful attention can improve tractor performance and affect traction power costs.
- Not all farm tractors are optimally ballasted.
- Not all tractor tires are correctly inflated for best tire performance.
- Not all farmers effectively use their available horsepower.
Ballasting advice: “On ballasting, you want your tractor weight to be right for your operation and conditions,” says Reed Turner, consulting engineer at AgTech. “Manufacturers typically give a recommended weight range in pounds per horsepower. The recommendation for a 4WD can be from 85 to 125 lbs./engine horsepower.” Rubber track machines generally have different recommendations.
Turner says rubber tire tractors typically are most efficient pulling at levels around 40% of their total weight and track tractors at around 45%. “This means your tractor should weigh about 2.5 times the load it’s pulling,” he says.
“Commonly, 2WDs are ballasted to be 25% on the front and 75% on the rear. MFWD should have 40% on the front and 60% on the rear. Four-WDs are usually 55% on the front and 45% on the rear,” he says.
So should you ballast with fluid or cast iron? Turner says either will work. Fluid costs less and has a stiffening effect on tires that can be used to help control power hop, but can be a nuisance to move around or adjust. And it tends to corrode valve stems and rims. If you use fluid, make sure you spread it out equally in all the tires on a given axle.
Cast iron costs more and doesn’t do as much for power hop, but it’s easier to add and remove.