Poor road or wind conditions

Misaligned front wheels

Inspect the alignment. Refer to Wheel Alignment Specifications in Wheel Alignment.

There is an unbalanced steering gear valve.

If the steering gear valve is unbalanced, the steering effort will be very light in the direction of the lead and heavy in the opposite direction.

Replace the steering gear valve.

The steering shaft is rubbing the I.D. of the shaft tube.

Align the steering column.