Keep in mind the wind and the road conditions.

Test the vehicle, going in both directions, on a flat road.

The front wheel alignment settings are incorrect.

Adjust to specifications. Refer to Wheel Alignment Measurement in Wheel Alignment.

The steering gear valve is unbalanced (if this is the cause, steering effort will be very light in direction of lead and heavy in the opposite direction).

Replace the gear valve. Refer to Steering Gear Valve Replacement - Off Vehicle in Power Steering System.

The steering shaft is rubbing against the inside diameter of the shaft tube.

Align or replace the steering column as needed. Refer to Steering Column Replacement in Steering Wheel and Column - Standard or Steering Column Replacement in Steering Wheel and Column - Tilt.

The tire pressure is low or uneven.

Inflate the tires to the recommended pressure. Refer to Tire Inflation Pressure Specifications in Maintenance and Lubrication.

The front or rear brakes are dragging.

Adjust the brakes.

The spring is sagging or broken (RWD).

Replace the spring. Refer to Front Coil Springs Replacement in Front Suspension.

The torsion bars are sagging (F4WD).

Adjust the torsion bar. Refer to Torsion Bar Replacement in Front Suspension.

The front wheel alignment setting (camber) is incorrect.

1. Check the camber setting.
2. Align the front wheels as needed. Refer to Wheel Alignment Measurement in Wheel Alignment.