As alloy wheels age, particularly in climates where a lot of road salt it used, rim leaks can develop as the lip of the wheel corrodes beneath the sealing bead of the tire. We’ve had that happen on two different older cars, to the point where on the TSX, I got disgusted with fixing four flats within a year due to rim leaks and ended up replacing the wheels with a set from Tire Rack.
I didn’t spend much on the wheels, but they were the second least expensive, and were of a sufficiently high quality that they look nice and appear to be durable. We also downsized from the skinny 17″ tire to a slightly fatter 16″ tire which, in this area, is helpful given the rough roads and many potholes–that extra cushion comes in handy and will help prevent bent wheels.
As for the old wheels, cleaning the corrosion with a wire brush or Roloc disc will work, but will not last. One of the rim leaks on the TSX happened a second time within the year. Some tire shops will put that black sealant on the rim before mounting the tire, but that is still no guarantee the rim won’t corrode beneath the sealant. It’s almost like painting over rusty metal.
Likely, only a full refinishing of the wheels would cure the corrosion. I’ve considered it, as they are usable on the CR-Vs in our hooptie fleet, but really have no reason to mount a second set of tires at this time. Refinishing these wheels (perhaps with powdercoating) might end up costing more than just buying another new set of wheels.