If the 4wd isn't disengaging, to me it sounds like one of the hubs isn't turning off. The front hubs are actuated by vacuum when you place it in 4wd. If the hub is dirty or damaged, it may engage and then not disengage. When you say it isn't pulling correctly, it makes me believe there is one side that is sticking.
Have that checked.
Wednesday, March 10th, 2010 AT 1:25 PM