I am attempting to attach a hitch to my 2010 Corolla S for a bike rack. The hitch I got was supposed to fit, the bolts that came with it appear to be slightly too big though. On two of the slots I can get them started just barely, and can't at all on the other slots. What size of bolt exactly do I need?
Have you checked to be sure the holes are still open and can accept the bolts to be threaded?

On my son's 2005 Corolla, we had to retap the holes to clean them up. We live in Minnesota and the weather took its toll on them. No big deal, we re threaded them and his hitch is still fully functional.