I parked in a spot which was iced up. Rear tires were spinning, so I engaged 4WD and pulled out slowly. As I accelerated, the truck started vibrating and when I coasted, it felt like the front brakes were engaging. Never happened before, so I disengaged, backed up and now in 2WD. Got home and tried 4wd and once again, started vibrating and when coasted, you can feel the truck slowing as if the brakes were being applied.

Now, I'm not sure, but I did get a wheel alignment about 4 month ago and have not engaged the 4wd till now. Is it because of this or is it something else?

Thanks for the help