OK so this is the deal. I just got this car about 2 months ago and I had a slight vibration when I go between 45 and 50 mph. Lately it has been getting REALLY bad. I bought this car from a friend and he told me that it was doing it when he got it and what he use to do is (because it's automatic) is just down shift a gear and it would go away. SO, I started doing that and it helps out a lot with the shaking but I also use up more gas having to drive it with my RPM's that high. Can ANYONE please help me with this issue??????

 

Might want to have your fuel injectors checked, is the vibration coming from the engine activity?

 

front end alinment maybe. what kind of transmision mount do u have. the solid poly ones will transfer vibration bad. look under car were the driveshaft goes into the trany, in that area theres a trans mount that holds the trany in place. is it solid or can u see though it. what color is it. if its red u have a poly mount (i think they make a solid mount in black to) and need to get a stock one. stock mount is like 10 bucks.