Many discs are needlessly replaced when the customer complains of brake vibration. Before replacing discs, be sure to check the condition of ALL steering & front suspension components: tie rods & ends, ball joints, struts, wheel bearings, calipers, ALL suspension bushes, etc. Some vibra- tions can also originate in the driveline; be sure to check u-joints, cen- ter support bearing, bearing holder, and trans mounts before blaming the brake discs. And NEVER, EVER use an air wrench to tighten the lug nuts!!!!