I recently picked up a '95 Passport as a utility vehicle and am trying to sort out a few items as well as preventive maintenance. So far, I'm impressed with the car. However, at times, very intermittantly, while in 2 wheel high, the LF hub attempts to connect and makes a **** racket for a few seconds and then quits. I dissassembled the hub to find the rear seal gone, but still had grease in sufficient amount. Upon inspecting the locking gear ring teeth, there is some definite wear. I completely cleaned & re-packed the hub. I'm worried that there may be another problem and don't want to trash the hub.

Any suggestions? Also, I have a Haynes manual which states there is "vacuum shift motor" that appears to be mounted to the front axle from the pics. There's definitely not one on this car. Am I missing something????