Been using PB Blaster...but will have to try the home brew.

 

The WD40 being just under "none" doesn't surprise me. Their marketing is great, their product is marginal at best. It is also highly flammable...

 

WD-40 ................... What a Joke!

 

I work on/restore old cars/trucks & boats (into trucks right now and another old boat).An old guy turned me onto Deep Creep a few years ago when I couldn't get a cast iron threaded 4" exhaust flange loose that hadn't been removed since 1952 when Chris Craft installed the motor. I had been using PB Blaster and some heat. I used the Deep Creep and got it and the 4 bolts screwed into the end of the exhaust manifold loose without breaking any off. With any penetrating fluid, patience is the key. Sometimes it takes a few days.