Does WD- 40 always leave a residue permanently behind or do they eventually evaporate?
Yes, it does leave a 'permanent' residue, of sticky crud.
I have been told a long time ago that it rots rubber.
It's actually the hydrocarbon 'carrier' it contains [very close to kerosene] which does that.
Is that an XB coupe you are talking about Norm?
I'd love a 77-78 XC Falcon 500 four door sedan with bog standard 4.1 crossflow six and column shift auto. I have simple tastes.
An old automotive engineer mate of mine [sadly now deceased] had a TD Cortina with 4-speed manual box, LSD and 4.1 crossflow, and he'd fitted it with a 2V head etc. That thing went like stink! He'd set up the front end to his own specs [not Ford's], so it handled very well, too.
