As a farmer who has dealt with rusted fasteners for all my life I can safely say I have never found anything any better than Zep45, in the mostly white can. I, personally, think it's better than acetone/ATF. Old exhaust manifold bolts can be tough, Zep is tougher. Repeated applications + patience, lots of patience = success.

SRH


May God bless America and those who defend her.