Originally Posted by onehundred80

Re-threading is not the answer at all, you need inserts put in the hub to replace the thread, Helicoil or Keenserts (which is my favoured option). It must be done accurately or the wheel will not bolt up tight with the ball on the bolt not aligning to the ball socket in the wheel, so it would have to be done in a vertical milling machine or similar.
What you have is weak, a new hub is probably the cheapest way out.