Changing the wheel offset
 

Can you change the offset of the wheels? Like I read you can shave off a little from the back padding of the wheel. Can you do this? If you can, where would you go to have this done? Or can you do it yourself by sanding or grinding?

I really want to lower my car, but I have 38mm offset on 18" rims and I'm afraid it will rub.

Yes it can be done, but DO NOT DO IT by sanding or grinding...

You need to take the wheel to a machine shop or wheel repair shop that has the equipment to do it correctly and uniformly...If you do it yourself you will have different offsets throughout the wheel's mounting surface, which will unbalance the wheels rotation and will ruin a number of different things...

with the offset of your wheels i would say your out of luck. You will need to shave at least 8mm off to be safe of rubbing, which could potentially grind into the spokes themsevles. I don't have any experience with this and don't know the design of your wheels. but from what I have heard you can't grind much off of a wheel and have it maintain structural integrity...