Messing around on some muddy roads today, and figured I would try out the different combinations of locked/unlocked diffs. '99 with center and rear diff. Center diff locks when pressing button in 4H (only did from a stop, can you do this while moving?) or automatically in 4L. Try rear, when in 4H just flashes never stays lit, tried several times. Go into 4L and first 10 times flashes only, then once it actually stays on. Try to then disenage and re-engage, never get rear to lock again. Muddy road, going straight. Speed range from crawl to 20Mph. Is there a sequence I need to follow to get rear locked everytime? SHould rear lock only in 4L?