Brake cleaner for diskbrakes unless it's a sound of metal on metal and you have to replace the brake pads. And for rim brakes if there's a metal sound a stone is stuck in the rubber part of the brakes, either get it out or replace as well if it's already worn down a fair bit.
I have much better luck with PB Blaster. I can't count how many rusty old nuts and bolts I sprayed with WD-40 only to have to follow it up with PB Blaster to get the job done.
PB Blaster is the product everyone thinks WD-40 is. Even still, I wouldn’t use it in the place of real oil/grease/lubricant but in a pinch it’s far better than WD-40 for those odd chores.
For sure. PB Blaster is my go-to when I find a bolt on my truck that hasn't been touched since it left the factory in '88. Its a quick fix for a stuck bolt, but still not a great solution for a squeaky door hinge.
It does to the US government... trademarks are industry-specific. It is absolutely legal for people to use the exact same trademark for different classes of business.
Of course they could still probably sue you into oblivion anyways, even if they're wrong.
The fact that they make spray lubricants and you have a website re-loader will likely not make any difference to them.