Ford Ranger 4x4...not

#1

My 98’ Ranger has been draining my check book. I have worked on the hubs, and had a couple of “mechanics” give it a go. They temporarily get it to work.

The dash lights show the switch from 2 to 4 wheel drive. Then the noises and no traction, comes. Occasionally the switch works and the traction is there. Then to switch back to 2 wheel drive I have to stop completely and back up for the grinding noise to stop. The vacuum actuated hubs are the issue, but where the leak is or how to fix it is baffling me and the “mechanics”.