Just finished putting a remanufactured engine in my stang. Everything runs great except this vibration. The vibration isn't too bad until the car is put into reverse. The minute I shift into drive or neutral, the vibration minimizes. I have no idea what it could be. The engine mounts and the transmission mounts were replaced during the motor swap. I also put in a new vibration damper. I've rechecked all of the bolts numerous times. I took it to a transmission specialist to ensure that the torque converter wasn't loose. Any ideas??