One of my rear brake disks is a bit rusty (~25%), the other slightly rusty. I investigated as the car was making the tell-tale rusty brake squeal. As usual, I thought it was the front - but the disks are clean. I noticed on the forum a couple of Toyota Service Bulletin for the Gen iii US model - but is there a known issue with shims on Gen ii European models (with disks)? It's true that I don't use the car a lot, and it's parked outside - so it's no shocker if I have a bit of surface disk rust - but normally driving a few KM should clean rust off a disk. N.b - I've tried putting the car in neutral and braking - and even tried downhill and applying the Park brake. I think the latter has helped, but it's a worry that I have to do that, especially heading into winter. (I have to say, the back disks look surprisingly scored for a car that supposedly does a lot of regen braking.....but if there *is* a shim issue, then it would contribute to scoring IMHO) I bought the car in April (registered Dec 09), it has nearly 38k km. I've probably done about 1000km since I got it.