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Pre-Alignment Information

NOTE: A normal shim pack will leave at least 2 threads of bolt exposed beyond the nut. Difference between front and rear shim packs must not exceed .30" (7.62 mm) on "G" series.
  1. Caster and camber can be adjusted in one operation. Check and set wheel alignment with vehicle in its normally loaded condition. Trucks which are consistently operated with heavy loads should have toe-in adjusted with truck under heavy load.
  2. On "G" series, jack up frame to raise wheel off ground. This allows upper control arm to drop far enough to use a socket on the nuts and permit shim adjustment. On G30 models (with 7/8" nut), remove upper control arm bumper.
  3. Toe-in must be checked AFTER changing camber and/or caster. Before adjusting caster and/or camber angles, raise and release front bumper twice to allow vehicle to return to its normal height. See RIDE HEIGHT article.
  4. On "G" series, caster specifications are given with a frame angle of zero. It is necessary to know the angle of the frame (whether "up" in rear or "down" in rear) before a corrected caster reading can be determined. See CASTER ANGLE DETERMINATION  .
  5. Adjust specifications if applying them to vehicles with any frame angle other than zero. Camber and toe can be read "as is" from the alignment equipment.