At RJ Race Cars whenever it is possible we use these Urethane Transmission Mounts (originally a GM style design) to mount the rear of the transmission.
These urethane mounts have a unique, metal safety locking feature, effectively controlling torque. This feature delivers the extra strength to resist problematic torque forces. Depending on the vehicle, these mounts can be used on both automatic transmissions and manual three, four, and five speeds.
The interlocking feature of the mount gives added confidence against drivetrain and frame damage, and yet are still soft enough to reduce the stress and binding that can occur with solid mounts.