GM Service Manual Online
For 1990-2009 cars only

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. Measure the engine movement at the engine mount in order to check for damage to the rubber portions of the mount.
  2. 1.1. Apply the park brake.
    1.2. Start the engine.
    1.3. Firmly apply and hold the primary brakes.
    1.4. Have an assistant stand to the side of the vehicle in order to observe for engine movement.
    1.5. Slightly load the engine, shifting from drive to reverse a few times.
    1.6. If the engine moves more than 24 mm (0.945 in) from the rest position, in either direction, check for loose, or missing engine mount bolts in the following locations:
           - Engine mount to engine
           - Engine mount bracket to frame
           - Engine mount to engine mount bracket
  3. If a engine mount bolt is missing, replace the bolt.
  4. If the engine mount bolt torque is within specifications, check the condition of the engine mount.
  5. Replace the engine mount if any of the following conditions exist:
  6. • Heat check cracks cover the rubber cushion surface.
    • The rubber cushion is separated from the metal plate of the mount.
    • There is a split through the rubber cushion.