This might be a dumb question but couldn't you just get some strong U-Bolts from the local hard wear store (Maybe some grade 8 if they even make them) and use some blue locktight (red is very strong and might not come off J.I.C you were wondering) or locknuts to keep it on. Or are the u-bolts on vehicles made a different way.

 

this is an old thread but i just had to answer the question above about making your own u-bolts..... HELL NO. do not perform shade tree heating and bending on u-bolts. you need to buy properly tempered and tested bolts. your life depends on it. some people insist on always buying new bolts and to each his own, but i've used and re-used junk yard u-bolts before. you can debate this, but do NOT make your own bolts.