It only happens when I first get in my car in the morning and it usually happens after it rains. When I go to back up though, once I hit the brakes a loud sound comes from the back of the car. Once I get going it doesn't happen for the rest of the day. Ideas?

 

I have the same problem and my one friend said it had something to do with the e-brake

 

Normal brake noise. Reverse goes against the wear pattern and usually has a high-pitched squeal or whine or a variety of noises, as you said, the first time or two. Worse after it rains, because there is more crap on the rotors (rust, etc) and more stuff to make contact/noise.

Don't worry about it, you can't fix it, it isn't hurting anything

 

i had the same thing happen to me and yes it only happens after it rains and when i back up only not when going forward lol i thought there was something in my trunk.