GM Service Manual Online
For 1990-2009 cars only

Engine Mount Inspection Front


Object Number: 2491  Size: SH

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

  1. Inspect for loose or missing bolts at the following locations:
  2. • Engine mount to the engine
    • Engine mount frame bracket to frame
    • Engine mount to engine mount frame bracket
  3. Replace missing or loose bolts.
  4. • Refer to Engine Mount Replacement .
    • Refer to Engine Mount Replacement Front Left.

    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.

  5. Using a suitable engine lifting device hooked to the eyelet on the accessory mounting bracket, raise the engine in order to complete the following tasks:
  6. • Remove weight from the mount.
    • Place a slight tension on the rubber cushion.
    • Observe the mount while raising the engine.
  7. Replace the mount if the following conditions exist:
  8. • Heat check cracks cover the hard rubber surface.
    • The rubber cushion is separated from the metal plate of the mount.
    • There is a split through the rubber cushion.

Engine Mount Inspection Rear


Object Number: 4569  Size: SH
  1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Notice: Broken or deteriorated mounts can cause misalignment and destruction of certain drive train components. When a single mount breaks, the remaining mounts are subjected to abnormally high stresses.

  3. Push up and pull down on the transmission extension housing. Observe the transmission mount.
  4. Replace the mount if the following conditions exist:
  5. • The rubber cushion is separated from the metal plate of the mount.
    • The mount has bottomed out.
    • The extension housing moves up but not down.
  6. Inspect for loose or missing bolts.
  7. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  8. Replace any missing bolts or nuts.
  9. If a mount is loose, tighten the bolts or nuts that attach the mount to the transmission or to the crossmember. Refer to Engine Mount Replacement (Rear) .