#GMTM-S / #3.1158G. GM Short Height Transmission Mount 1 5/8 Inches Tall. Fits 4L80E and Others. Polyurethane transmission mount fits most gm rear wheel drive transmissions installed height of 1.62″.The stock height is 2″. Mushy stock rubber transmission mounts can’t take the torque and vibration of high performance street and race use. Energy Suspension polyurethane transmission mounts last longer than rubber, can handle more horsepower, and are soft enough to absorb vibrations.
Use this mount with the 4L80E GTO conversion crossmember. Energy Suspension 3.1158G GM Transmission Mount, Black Short Performance Polyurethane, For Use with Custom Applications, GM Transmission Mount.