I have looked through the towing section of the forum and have not found a clear answer, sorry if this has already been visited. I have a 2006 tundra double cab SR5 with the factory tow package installed. I purchased a ballmount and have towed a few things with it. My only problem is the ball mound rattles around a lot making a bunch of noise. I measured the receiver and it is not 2'' by 2'', it is 2 1/8'' by 2 1/8''. That adds an extra 1/16 of an inch around the entire ball mount making the ballmount really move when I tow a trailor or boat. I don't think it is a safety problem, I just want to be on the safe side. Can anybody tell me if I need to get a special ball mount or a fix to make the ballmount stop rattling around so much? Thanks in advance.