I recently replaced my 15" stock rims with 17" Cross Spoke rims on my 97' non-sport E39. The ride is very rough on even highways. I drove a 540i Sport 99' yesterday with the same wheels on it and the ride was very good. Not harsh at all. The dealer checked my struts and said they were fine. I have come to the conclusion that I might need to upgrade the struts and springs for a smoohter ride. My PSI is 33f/35r. Also, car is very unforgiving on slight humps in the road. It pulls harshly when I go over a small hump. Any ideas of what I can do using after market products or OEM parts would be GREATLY APPRECIATED!!!!!!!!!