Well I noticed today on the highway that something I noticed during the test drive was getting much worse. Does anyone have this feeling where when the car is coasting in gear at maybe 45 mph and is experiencing engine braking (not pushing the gas) around 2500-3000 rpms or so and then all of a sudden a strong vibration will appear that is strong enough to shake the shifter and seemingly the steering wheel? It also sounds kinda like a truck using a jake brake but not nearly as loud.

Is...

Strange Rumbling/Vibration when coasting in gear (no gas), 2012 Mustang V6 PP M/T