the mount is located at the rear of the tranny and it's easy to change. the vibration may feels like it's from engine or thru out whole car but it's not. what car do you have ? i had changed my engine mounts (expensive) prior to changing the trans mount. i couldn't figure it out so i took it to a local mercedes specialist shop and the guy told me to change the trans mount(i'm a gm tech) and when i took it out it was broken in half, put new one in and smooth as silk again.