B+W is the way to go. Thin coat of grease, like mentioned before does keep it free. And yes, You can get the ball out if it does happen to rust in. Spilled some fertilzer in the back of my truck, got the truck rinsed out well but forgot to take out the ball and wash around it. Rusted in tight. Got under the truck with an 8# sledge and gave the ball a couple of wacks and it poped right out,