New suspension
 

So i recently got some new wheels and tires.

18x8.5 30offset
255/40r18

And i got my rear fenders rolled to make sure they wouldn't rub. After getting my fenders rolled with 2 people in the car (including myself) the rear left would rub against something that sounded plastic. I got out of the car and check and it was the plastic piece that goes to the bumper. The strange thing is that the right side doesn't rub at all.When im driving by myself and take quick turns or hit a dip the rear left is the only one that rubs. One of my friend mentioned that the rear left strut could be leaking. If i sit in the driver seat the rear left side goes down alot but if i site in the passenger side the rear right goes down just a little. So my question could it be true that my strut is going out, is there a way to be sure. Also im a little tight on money right now and since i was thinking of getting aftermarket suspension should i just go with the aftermarket. I was thinking of getting koni yellow struts. Has anyone ran kony yellow struts on oem springs? Is that a good idea?

People run Koni struts with OEM springs all the time. You will be doing the same install for springs later on though, if you go that route. I wouldn't think your car should rub like that if you have stock suspension, so the strut may be going out. Post some pics of the wheels! FYI, you don't really need that black plastic piece. I cut most of mine off. There is a mounting tab for the rear bumper under it that some people have taken a grinder to in order to make lower offset wheels fit on really low suspension setups.

^thanks for the info and this is the best pic i have right now

http://img.photobucket.com/albums/v2...140CST2010.jpg