Let's say you've got an old nut stuck completely ... to get deep enough to loosen them. In this case, it's time for a different workshop fluid to step in: penetrating oil. When rust is too thick ...

That’s why whenever I work on a car with rust, I keep a can of penetrating oil by my side. Never Lose Another Bolt Again With This Tool Extendable Breaker Bars Make Loosening Nuts Easy These ...

However, if the nut and bolt are very old and oxidation has taken its toll, WD-40 may not be able to get deep enough to loosen them. Penetrating oil — also known simply as penetrant — is ...