I'm already used penetrating oil, but doesn't work.

the nut of the frame side is comming out, but I can't take out the bolt, witch should be take out by hand directly.

 

which one? got a pic?

for stuck nuts thats really stuck, assume there is no rubber around. i always just burn the **** out of it with a small propane torch till its red, then toss it with iced cold water, it comes out right away

 

pb blaster is the best there is, Worth its weight in gold. try that

 

Or 50/50 acetone and ATF