Key points to saving fuel during tractor field use are keeping a current maintenance schedule, proper ballasting and tire inflation, and selecting a fuel saving gear and throttle setting.

Keeping your maintenance schedule current as suggested in the tractor owner/operator’s manual will improve fuel economy. In a Missouri case-study, replacing air and fuel filters on tractors brought in for dynamometer testing lowered fuel use by about 4% for the same power output.

Although recognized as important, tractor operator’s often don’t check total tractor weight or front- and rear-axle ballasting. Proper ballasting enables the tractor to efficiently transfer power to the drawbar and avoids wasting energy. Total tractor weight required depends on tractor style (true four-wheel drive, mechanical-front-drive, or two-wheel drive) and field speed. Use your tractor manual or see table 1 for suggested pounds per tractor horsepower. Having this weight properly split between the front- and rear-axle also affects efficiency. Proper weight split is affected by tractor style and whether the attached implement is pulled or mounted. Check the tractor operator’s manual or see table 2 for suggested guidelines. Using cast-iron weights allows ballast to be removed for fuel savings in lighter drawbar work (e.g. spraying).

Tire inflation pressure should be correctly adjusted for the load the individual tire is carrying. Consult the tractor operator’s manual or check with the tractor or tire dealer as correct inflation pressure for a given weight depends on tire size, use as a single or dual, and if the tire will be used at high speed (e.g. greater than 25 mi/h). Most operator’s are aware of the damage under inflation can cause to tires. Over inflation contributes to excessive wheel slippage and fuel use.

For lighter drawbar loads such as moving equipment, spraying, and lighter tillage (e.g. rotary hoeing, row-crop cultivating, or field cultivating if implements are not too wide or operated too deeply) shifting to a higher gear and reducing the engine throttle setting will reduce fuel use per acre. If using the power-take-off (PTO) such as with a windrower or baler, engine speed will need to be maintained at the rated PTO speed. Some newer, high-horsepower tractors use electronic controls to automatically shift to a higher transmission gear and reduce engine speed to maximize fuel economy while also maintaining correct PTO shaft speed for PTO applications.