GM Service Manual Online
For 1990-2009 cars only

Engine Mount Inspection Front

The following procedure is used for diagnosing the front engine mounts.

    Notice: When raising or supporting the engine for any reason, do not use a jack under the oil pan, any sheet metal, or the crankshaft pulley. Due to the small clearance between the oil pan and the oil pump screen, jacking against the oil pan may cause the pan to be bent against the pump screen. This will result in a damaged oil pickup unit.

  1. Raise the vehicle. Support the vehicle with safety stands.
  2. Raise the engine in order to remove the weight from the mounts. Place a slight tension on the rubber cushion. Observe both mounts while raising the engine.
  3. Replace the mount if any of the following conditions exist.
  4. • The hard rubber surface is covered with heat check cracks.
    • The rubber cushion is separated from the metal plate of the mount.
    • The rubber cushion is split through the center.
  5. Lower the engine if there is movement between a metal plate of the mount and its attaching points.
  6. Tighten the bolts or nuts attaching the mount to the engine, the frame, or the bracket.

Engine Mount Inspection Rear

The following procedure is used to diagnose the rear mounts.

  1. Push up and pull down on the transmission tailshaft. Observe the transmission mount.
  2. Replace the mount if any of the following conditions exist.
  3. • The rubber cushion is separated from the metal plate of the mount.
    • The mount is bottomed out (the tailshaft can be moved up but not down).
  4. Tighten the bolts or the nuts attaching the mount to the transmission or crossmember if there is a relative movement between a metal plate of the mount and its attaching point.
  5. Lower the vehicle.