I got my front brake caliper disassembled and cleaned. The piston took a lot of work to get out, but I finally did. I noticed two spots on the piston where there was some pretty deep rust. I just ordered a new piston. I did try to put the old piston in just a little bit to see how easy it would be. The rust is very close to the open end, so I was not attempting to put the piston in enough to get to the rust spot. I used brake fluid to lubricate the piston, then tried to push it in using my hands. It would not budge. I tried twisting, then I tried a little bit of pressure from some vice grips. I did not really go at it with the vice grips, because it seemed like it should not take that much force to get it in. So how much pressure should it take to get the piston back in? Has anyone else had this issue? Is it possible that my piston or the hole in my caliper has deformed somehow? I am pretty sure everything was very clean.