with the hubs locked in I can drive the truck and have no problem, as soon as I pull the lever back and put it in 4 wheel drive it starts to squeal almost sounds like a fan belt slipping also the steering wheel and front end vibrates and makes a humming noise. any ideas? if I pull the lever without the hubs locked in will that spin just the transfer case and ring gear in the front hub? I bought the truck about a month ago and trying the 4x4 out in the field I didn't notice anything but I can definitely tell there is an issue driving it down the road, it is a pretty violent vibration and noise.