transfer case or tranny problems

[dumper209]

how it going? i was on my way home from school today when all of a sudden i had a shaking and grinding coming up from the 4x4 shifter. it seems to go away when i am cruisin but as soon as i give it gas it starts to do it and it shakes and grinds really bad when i let off the gas. i touched the shift know when it was doing this and it felt like something was grinding. i am just wondering what it could be anyone have any ideas? and when i get under the truck when its on it makes a loud ticking sound coming from the tranny transfer case area.