Vibration

[iamkrista]

About 2 weeks ago, my back wheel came into contact with the curb as I was making a right hand turn - in a parking lot where the curb stuck out strangely. I heard a loud bang (I was driving pretty fast for being in a parking lot). I examined my 2008 Boxster and could detect no visible damage. When I drove it after that, I noticed that something felt off. The seat seems to have a slight vibration and the car feels, well, unbalanced and bumpy. The steering wheel does not vibrate though. I have driven this car every day since I got it when it was new and it was always perfect. It feels different now. I took it to a tire shop and had them look at it. They said my alignment was off ever so slightly and they claimed to have fixed it, but when I drove the car, it still felt off in just the same way. I took it to the dealership and they looked at it and they drove it and told me that my tire pressure was too high and that would make the ride seem bumpy but it was fine other than that. I know that something is off though! Like I said, I have driven this car every day for almost 5 years and I know that something is wrong! Am I crazy? The ride was never bumpy like this before. The ride used to be smooth and comfortable. It was a joy to drive. Now I dread it. If I just need the wheel rebalanced, wouldn't the tire shop have realized that? What else can be wrong? Please help!