Sounds like one of the mounts is not properly centered. One of them sets the position of the engine, left to right. With the engine off center, one of the pulleys can rub on something, or the two metal pieces of the mount can contact each other. Those two pieces are separated with a rubber isolator, or insert. If they touch each other, normal engine vibration will be transmitted into the passenger compartment where it can be heard and felt. The clue is this just started when the mounts were replaced.
Wednesday, September 13th, 2017 AT 3:11 PM