I'm looking and test driving a F-150 crew cab 4x4. Well I found after the first day of driving that there is a whining noise . I got the truck in 2H by the switch inside but when I look underneath I find that the driveshaft on the transfer case is still to be engaged because the shaft is not spinning freely when I try to turn it. It seems to be still engaged even when I have switch on 2H.. do not know how long the previous owner drove it like that. The truck has little over 80,000 miles on it.. Has anyone had this problem and what did u do to get it working?2007 F-150 supercrew cab 4x4.