Tires: poor ride - radial force variation, sidewall stiffness, car steering wheel, firestone firehawk

Question
Hi. I hit a pothole a few weeks ago hard enough to bend the right front aluminum wheel on my 2002 Nissan Sentra SE-R. After, I noticed a fairly heavy vibration in the steering wheel at just about all speeds as well as a "not smooth" ride. I took the car to my local garage (been going there for years) and he said that right off the bat he thought the problem was a bent wheel from what I was describing. He did find this to be the problem (I saw the bent wheel myself) and I bought a new wheel. In the meantime from when I ordered the new wheel to when it came in and was mounted, I had him put the bad wheel on the right back of the car. Steering wheel vibration all but disappeared but ride was not good. Then the new wheel came in and was mounted on the front right of the car with the old tire (Firestone Firehawk XGA 205/65/16). Now, I don't notice a vibration in the steering wheel at all speeds but I do notice it as I accelerate closer to 70 mph. And I notice that the car has an extremely poor ride even with the new brand new wheel on at all speeds. I can distinguish between the "road noise" and a low-level constant un-even & bumpy ride, especially when travelling at speeds in the 40-50 mph range. It seems that this bumpy ride translates into vibration at higher speeds but is not actually "vibration" at lower speeds. I have read some information on the web about radial force variation being the cause of vibration and poor ride even on a perfectly balanced tire. I also read about a system that Hunter came out with that can simulate a road test on the tire to determine if this is the problem and if it is, corrects it by instructing a better mounting position for the tire on the wheel. Do you have any idea what might be going on with my car? When I hit the pothole could I not only have damaged the wheel but also damaged the construction of the tire? Should I take it to be tested on one of the Hunter machines? The car only has around 12,000 miles on it. Any assistance you can give is very much appreciated.  

Answer
Chris,

If hit something hard enough to bend a wheel, it is likely you also damaged other things.  At the very least you probably altered the alignment.

From what you've described, it sounds like there is a suspension problem, and all the symptoms point to this, even the vibration.  

However, you should have replaced the tire - it took a heck of a hit.  Could be on its way to a failure.

The first thing I would do is have the suspension checked.  It sounds like it is binding, perhaps from a damaged strut.  If you haven't gotten an alignment, get one.  Be sure to tell the folks they need to look the vehicle over very carefully.


Hope this helps.