2001 BMW X5 Squeaking noise

My suv is making an annoying squeaking noise that seems to be coming from my rear. It sounds like an old squeaky door. I noitce it when I am parking it or when i go over any kind of bump. Even when I park it and get out of it it makes s squeaky noise. I get it inspected in a few weeks should i just wait til then to have it checked? What do you think it could be? I thought maybe rear axle? Since we have had alot of snow and cold weather is when i have noticed it.
Thanks...