This is a very common problem with the 3rd generations Dodge 3/4 & 1 ton trucks. My 2005 2500 Hemi 4x4 needed 1 new ball joint at 31,000, then all 4 ball joints again at 63,000 along with tie rod ends. I ended up replacing the entire steering with the 2008.5 style steering as it was redesigned to be stronger.
Long story short, it is a weak point on these trucks. I am experiencing loose steering as it seems to wander a great deal while on the highway causing the driver to correct a lot to keep it going in a straight line. I believe the track bar bushings are bad as it is clunking while taking corners in the city.
If you have it torn apart while doing the ball joints you might as well replace the front axle u-joints as well, they are prone to wear out quickly.
Good luck..