Vibration felt at 35mph not front end
Hey guys, I am new on this forum so I apologize if this has been posted elsewhere. I am having some strange vibrations almost like the road is very bumpy. It happens from 35-40mph in third or fourth gear, then it seems like it happens again but less noticeable at about 65mph. The symptoms seem worse when I am coasting and not giving it any gas. In addition it is not as noticeable when the car is out of gear... I have had the car aligned, checked all front end components, wheels balanced and checked. Last thing the dealer said was to check the spark plugs and wires. Well I had already changed the spark plugs and wires because I thought that was the issue. Anyone have any insight? I am worried it may have something to do with the tranny. This is killing me because I am a grad student and do not have too much time to mess around with this.