Right front mag wheel is leaking down a few pounds per week. A few years ago I tried sealing a Nissan wheel that leaked down and sealant didn't help. Is it an aging thing? Is there something new out there that can make a better bead seal?

 

You need to have the tire dunked in a dunk tank to see where it is leaking from. It might be a valve stem or a nail in the tire. Or it could be the bead leaking.