2003 Ford Explorer
 

About a couple of months I've been driving my explorer with the transfer case making jerky and thumping noises, now all of a sudden 2 week goes by without any jerking or noise from my SUV. My explorer runs almost like new again. I am afraid to even touch the 4X4 buttons on the dashboard. I'll just leave it alone until I feel it again. Any one have some thoughts to this mystery? :)