The other thing that no one has mentioned is warping brake discs.
If you think about it, a river crossing is almost invariably down in a valley and is generally approached by driving down a (sometimes very steep) hill that will involve the use of brakes to some extent.
I remember Slunnie posting this up some time ago, along with the idea that vented discs were more prone to warping than solid if suddenly cooled.
cheers, DL

