^ good to hear that they found the cause and fixed it, though it does not seem normal to me for rims to rust, i have oem rims on my FX for over 5 yrs and TL without any issues, i hope this was in fact the reason and hopefully you wont have to pump in anymore air on cold winter mornings.

 

Yes, I certainly did not expect it to happen in a 30+K car - none of my other prior cars had such a problem. Here's something I found on the subject.

"This may sound a bit crude but cars delivered form the factory today with aluminum wheels the are susceptible to inner wheel corrosion and rust. They're made off-shore with no type of interior or exterior urethane clear coating. The tires must be broken down and the inner bead areas must be thoroughly brushed and "slicked-up" with scotch-brite pads before remounting and resealing with nasty-old black bead sealer. This takes a bit of work on someones part but this step will seal the tires once again.

The rust and corrosion rears its ugly head especially fast as plain air contains dirt and moisture. Consider having the tires re-inflated with nitrogen after getting the wheel beads cleaned and tires resealed with the black tire bead sealer. Nitrogen is an inert gas, there's no moisture and dirt. The molecules are enormous which resists bead and valve stem leakage. Nitrogen isn't as heat sensitive as plain air. You'll find tire pressures are more stable in hot and cold temperatures."

 

^ very interesting yet weird but nice to know for sure. I know the advantage of nitrogen but have been unable to find it anywhere in the area.