Alright, well I was out last night, we have had a good amount of snow this past week and it was snowing last night, 4wd has been working fine, ive been staying in 4hi, then all of a sudden last night when I go to accelerate it starts this baad grinding noise and it almost feels like I loose traction then it will stop then do it again.. any ideas? I searched but couldn't find anything really similar to what I was experiencing. Any help is appreciated. I have a 1998 F150 4x4