Ford Ranger: Clunky transmission

I have a PX Ford Ranger Mark 2 XLT auto that is almost out of warranty. Sometimes it doesn’t select Drive or Reverse, and when finally it does it makes a loud CLUNK. I took it to my local dealer this time last year and they reset all the computers, but it has just started happening again, and I am taking it in next week for a warranty check.

How do I go about any future problems after the warranty period expires if they can't fix the issue?