I have come to a conclusion that the reason for the horrible gas mileage, and the sound of the front driveshaft spinning is that my 4x4 isnt disengaging. I have manual hubs with pushbutton 4x4, when i push the button for 4x4 i dont hear to feel it engaging, but lowrange i do. Is there any ideas to test this for sure, also it feels like my truck is very slow/weak. What could be causing this, the electronic switch motor on the TC? If so is it hard to replace or expensive? Thanks.