GM Service Manual Online
For 1990-2009 cars only

Notice: Broken or deteriorated mounts can cause misalignment and eventual destruction of certain drive train components. When a single mount breakage occurs, the remaining mounts are subjected to abnormally high stresses.

Front Engine Mountings

    Notice: When supporting the engine to replace a mount, raise the engine only to the height required to provide clearance for mount removal. It may be necessary to drain the cooling system and disconnect hoses to avoid damage when the engine is raised. Be careful that control cables and wiring are not damaged from raising the engine. When replacing a single front mount, both mounts should be detached before attempting to raise the engine. Failure to do this will place excessive stress on the attached mount when the engine is raised.

  1. Raise the engine to remove weight from the mountings and to place a slight tension on the rubber cushion. Observe both mountings while raising the engine.
  2. Replace the mounting if the following conditions exist:
  3. • Hard rubber surface covered with heat check cracks
    • Rubber cushion separated from the metal plate of the mounting
    • Rubber cushion split through the center
  4. If there is movement between a metal plate of the mounting and its attaching points, lower the engine and tighten the bolts or nuts attaching the mounting to the engine, frame, or bracket.

Rear Engine Mountings

  1. Push up and pull down on the transmission tailshaft. Observe the transmission mounting.
  2. Replace the mounting if the following conditions exist:
  3. • Rubber cushion separated from the metal plate of the mounting
    • Mounting bottomed out (tailshaft can be moved up but not down)
  4. If there is relative movement between a metal plate of the mounting and its attaching point, tighten the bolts or nuts attaching the mounting to the transmission or crossmember.