Appsy, I don't know if this has been mentioned before, but honestly, even if WD40 has penetrated the joint it will often do nothing. I am speaking from experience.
Drive down to Bursons Auto parts just off Joondalup drive and get a bottle of Penetrene aerosol.
Honestly, its one of the best $20 I have ever spent. I was soaking bolts in wd40 with no effect. I spray this on a few times and the come loose.
WD40 is a good water dispersant, but I cannot agree its a good lubricant like they say on the pack. Sure, it is good enough to stop hinges squeaking, but anything can do that
