Rough Ride at Various Speeds

[overwest]

So, another problem I've been having with my car since I've bought it was that at various speeds (mainly around 45mph or so), the car clunks aggressively as if a wheel bearing is going out or there is a horrible rod knock. At any other speed it seems okay, not so bad, the only other time I can feel the car shake as much is just in reverse. I'm wondering if it's either because my HICAS system isn't working properly (I can see it come on from time to time, as well as I know for a fact it's a lot worse in Sport Mode), or from the new wheel setup I have not being properly balanced. Or is it from a driveline, a wheel bearing, a motor/transmission mount, etc.

[frapjap]

What happens above 45mph? Does it come back at a particular speed again? Is it RPM dependent?
It could be as simple as balancing as you've mentioned. Find someone with a RoadForce balancer and have them zero them out. Even if that isn't the problem, it'll be a good piece of mind and you can eliminate that as a variable. It does sound like a bushing or motor mount might have had enough, too.

[overwest]

I did some freeway driving today and around 80 or so it was doing the same again, little bit quicker. The remedy I find is to just slow down/speed up. Just as long as I go down on the throttle it'll cut in and out. My 45mph is my cruise speed to school since its down the block from my apartment, but it's pretty bad even for just that short drive. It'll get real choppy, like the engine is going to give out any minute, and the car cuts out like it doesn't want to keep moving forward unless I give it more gas.