I used this tool to press in new ball joints into the front lower control arm of my 2007 Ford Explorer. It took me a minute to figure out the best cylinders and ends to use, but once I got going, the ball joint pessed in well.
A few tips... Grease the threads. Go slow. In my case, I used a torque wrench. When the torque jumped from about 70 ft lbs to 100 ft lbs, the ball joint was fully in.