Radial Tire Lead

Some alignment problems involving "lead" or pull to one side have been caused by off-center belts on radial tires. To diagnose this problem inflate tires to recommended pressure and drive vehicle both directions on an uncrowned road. Observe and note any "lead", then switch front tires and road test again. If "lead" is corrected without roughness, leave tires in position. If roughness results, replace tires. If "lead" reverses, install a known good tire on one side and repeat road test. If "lead" remains, install a known good tire in place of other front tire. If "lead" remains, recheck alignment. It may be necessary to adjust caster so that leading side is 1° more positive than other side.