Dry ice works better. Used to do it with valve seats and bearing races, really shrinks 'em up. Freezer works in a pinch beings dry ice is iffy here and comes from 120 miles away. Good suggestion though.Not sure if this has been mentioned anywhere but, when I slipped a new set of ball joints in my TJ I put the new ball joints in the freezer overnight (simple trick I learned years ago) because it makes them shrink slightly and they go in with hardly any pressure applied at all. Just sayin ;-)