I have a 2013 Prius v Three (lowercase v for Prius v not an uppercase and Three not III as Roman numerals were used for the 2010 Prius) model. Around 5k miles into owning my Prius, the brakes make a strange wailing noise in the cold. It doesn't last long and only occurs when it's really cold. Does anyone else have this issue? Does this mean I'm going to have brake problems in the future? I'm going to insist that the dealership keeps my car overnight and test it early in the morning. A new car shouldn't be doing this!
Do a search around here for "brake groan". They almost all do it when the brakes are damp. There's nothing wrong with your brakes, its just an annoyance. Disc brakes have been making strange noises for 40 years. You can harass the dealer until they do something, but they will resist because the brakes are functionally fine.
Thanks. Just sounds bad. Kind of embarrassing to drive a brand new $30k car that sounds like an old pinto!
Toyota USA has issued a service bulletin that describes this issue. It is T-SB-0081-13 June 28, 2013 "Rear Brake Groan or Squeak Noise when Cold" but there is now a Rev 2 of this published in Jan 2014. You can look for it using google search. You should be able to direct your Toyota service provider to this and have it remedied under warranty.