I have an 08 explorer 4x4, when I put it in 4 auto or 4 high it's like it's in neutral in all gears (wont move) then I put it in 4 low and it KICKS in and works fine, so it only moves in 4 low, if I push 4 auto or 4 high it does nothing but rev up when I hit the gas in all gears and when I put it in park it grinds as if I was moving