Which Penetrating Oil is Best? Let's find out!

If it wasn't eminently obvious, most of these "secrecy" programs are marketing fluff. The actual ingredients are literally on the safety data sheet: link The company can brag that their formulation has a special blend of herbs and spices, but someone who wants to can obviously make their own special formulation and say that theirs is secret too. More importantly, the proof of the pudding is in the eating. And there is nothing particularly special about WD-40's formulation anymore. WD-40 consistently performs worse than nearly any other available penetrating oil. ▶ this video It's a terrible long term lubricant (because it's designed to evaporate, it actually concentrates gunk and grime). WD-40 themselves have come out with improved "Specialist" formulations that mostly just copy other, superior products.

WD-40 is a penetrating oil. It's pretty decent at that[1] and not badly priced. It's a pretty "middle of the road" product at its intended purpose: displacing water and rust to loosen stuck fasteners (and other items). [1] ▶ this video

Project Farm tested 7 penetrating oils. ATF/Acetone ranked 2nd place above many specifically designed fluids. ▶ this video