driving to work this morning in the snow 4 wd engaged it felt a little funny. after work the roads had been cleared a little, but i still had the 4 wd engaged. everytime i would come to a clear patch, i would hear a growling coming from what seems to be the passenger front. soon as i hit the snow again the sound goes away and drives a little smoother. altogether in 4wd it seems to be acting a little squirrely. when i took it out of 4wd at highway speed it took a little time for it to disengage, and when it did it felt like i ran over a curb. 2wd seems to be running fine. any thoughts?