My 2001 outback (45k miles) makes a whistle sound at about 3700+ RPMs. I only get this when passing on the interstate or on hills. Passengers have describing the sound as coming from the rear of the car, which points to the exhaust. However alternative theories are that the fuel system is making the noise.
Does anyone else have this high-rpm whistle?
PS - I have seen reference to this problem before but it was always diagnosed as an exhaust issue. However, since so many people have seen it, I am wondering if the problem is more mundane.