Reverse does not work, but drive does

Help! Put vehicle in reverse; heard pop; vehicle would not move; drive/forward still works; have had noise from transfer case for several years, but Ford unable to locate problem.

Any suggestions?

What year and model? I have a 2002 XLS, 4.0L, V6, no such problems at this time. 59K miles.

Adam

Save all your Ford paper work from previous several years? Make them pay for the repairs since they can now probably find the problem.