when i put the truck into drive or even into reverse the truck makes a loud clanking which i have now found is actually both the front and rear driveshafts shifting as to the truck is put into either drive or reverse. most of the clunking seems to be coming from the rear of the transfer case, and it does not sound normal at all. also when i steer in 2wd the truck steers fine but if i put it into 4wd and try and steer theres all sorts of bad noises and hesistation from what also seems and sounds like the transfer case. suggestions, bad transfer case, what do i do now???