pitman arm won't come off

I've had a few like that. Tighten it up with the puller. When it won't move,
Rapp it with a 3lb. sledge hammer a couple times. The Rapping will help
loosen it. Tighten the puller up a little more, and hit it again.
After a few times it will start to come off.
Hit it around the other side away from the arm.
Belive it or not. It will come loose.
If all else fails. Heat it and hammer on it.