Recommended step-by-step procedure Firestone dealers and service people should follow to reduce or eliminate power hop on four-wheel-drive tractors, including how to determine minimum tire inflation pressures.

The overall goals in controlling power hop in four-wheel-drive tractors pulling implements are:

• Having a tractor with as close to a 51 percent front/49 percent rear static weight split as possible.
• Having tire inflation set to the lowest pressure that will carry the static axle load.

To accomplish this, you will need to soften the tire spring rate and/or alter the static weight split.

It is not possible to control power hop if the tractor is not equipped with duals or triples on both axles.

Step 1: Check Implement Adjustment and Drawbar Position. Check to be sure that the implement hitch and tractor drawbar are properly adjusted. This information can be found in the individual operating manuals for the implement and tractor. Once the implement hitch and tractor drawbar are properly adjusted, proceed to Step 2.

Step 2: Determine the Correct Axle Weight. Check for proper weight distribution. Get as close to 51 percent front and 49 percent rear as possible.

Remove any suitcase weights from the front and add them to the rear (if possible). The front tires must be dry. If needed, hydroinflate ALL the rear tires to 38 percent fill (4 o’clock or 8 o’clock position get the correct weight distribution).

Step 3: Match Inflation to the Load on All Tires. Set the inflation pressure on all tires, front and rear, to the minimum value needed to carry the static axle load. The individual tire load is determined by dividing the static axle load by the number of tires on the axle.

Stop & Test. Check the tractor for hop and performance. Most of the time, setting the proper tire inflation pressures will solve the power hop problem. However, if the power hop is still present, proceed to Step 4.

Step 4: Add 6 psi to the Front Tires Only.

Stop & Test. Check the tractor for hop and performance. If the power hop is still present, proceed to Step 5.

Step 5: Add 6 psi to the Rear Tires and Return the Fronts to Normal.

Stop & Test. Check the tractor for hop and performance again. If the power hop has now been eliminated, no further adjustments are necessary. If the power hop is still present, contact Firestone Field Engineering at 1-800-847-3364.