I'm using heim joints at the ends of my tie rod, and just found (after 15,000 miles) that the bolt on one end (passenger side) has loosened in the bores of the heim joint ball and steering arm. Because of their short length, the bolts I had used (stainless 1/2-20 x 2 1/2) were fully threaded, and I believe that the loose fit is because the threads run through those bores and have now "squashed down" a little.

What does everyone else use for this? Are there special bolts I should use, or should I use longer bolts with a solid shank and thread them myself so that no threads enter the bores?