Thanks ZaPPZion,
Yes unfortunately you are right, I tried this solution before (create 2nd physic body) but not easy syncron these bodies.
I thought that I create my collision physic body from two part lower and upper and attach them with together, after when I crouch I will turn off the collision of the upper body and so on. I'm already finish all of my FPS movement just this was the last problem.
I built a little stair finder function to my code, so If I want to go up on stairs I add extra force to my physic body. If I finished with my code I will share it. I have also the other version of my movement, but I think it will better than earlier.
