Totaly sounds like you are still in four, I have an '87 that used to have auto hubs and ocasionally after attempting to disengage them it would act like that, I had one side that wasn't disengaging. Auto hubs are complicated and more fragile than manual hubs. They take a while to engage too, so as you crawled over the rock pile I would guess that they engaged under a load as you were climbing the rocks, you probably broke or bent the tabs of the brake shoe spring. My advice would be to go to a wrecking yard and pick up a pair of manual free wheeling hubs, aisin are stock or warn and superwinch are ok too, and swap them out, Just grease em good.
This site has a good walkthrough at http://www.4x4wire.com/toyota/tech/autohub/
You will need slightly different parts to attatch the rotor to the spindle for the manual hubs. On an auto hub there is just one adjusting nut that holds the wheel on the spindle, on a manual there are two nuts and two washers. Just go to the Toy dealership and tell them that you want to swap the auto hubs for manual hubs. You will need from the inside out a washer/adjusting nut/lock washer/lock nut to replace the auto hub adjusting nut. Cost me fifty bucks for the hubs and thirty for the nuts/washers both sides. The whole procedure is pretty simple, took me less than an hour a side, you just need a torque wrench with the big ass 54mm or 2 1/8 socket for the nut and a hammer and punch to get the cone-core washers out of the hub, see the article for how to do this. good luck! I would be happy to help you through it if you decide to swap them out and have any questions, manual hubs are wayyyyy better and you will be glad you switched. Cheers! Tayo <img src="/forums/images/graemlins/cheers.gif" alt="" />