Here are pics of both rear wheels. Fronts show no damage.
I should have taken good pics when I got the vehicle last year to better determine if this corrosion is advancing (surely it is). Well I have them now.
These look ugly, but of course they will in close up high res photos. Not quite as noticeable in person.
Rear Driver
Rear Passenger
--> Battery update:
I also measured my battery voltage for the first time since getting the new one under warranty. I measured 12.2 volts. That seems low for a brand new battery?
Granted that was at the front jump points, which reads 0.1v lower than the battery terminals... but even 12.3 volts is low.