I just bought a 2001 Subaru LL Bean w/ 64K miles. Very nice ride, overall, though I have noticed two weird noises. First, when accelerating at highway speeds -- 70-80mph (with stereo OFF) -- I hear a high frequency noise that sounds electrical, ie., I think it's too high a frequency to be the tranny or the engine. Then when I take my foot off the accelerator and coast through 65-60mph, I hear a vibration from somewhere up front, sounding a bit like a rattle or a mechanical resonance. Neither noise seems to affect performance, though I wonder about long-term negative effects.

 

Any others out there have the same experience? If so, any insight into causes and solutions (besides turning the stereo back up)?

My parents had the same high frequency noise problem in their 3.0 Liter Jaguar. They had the car in and out of the dealer 3 or 4 times. We had the amp replaced, and the noise stopped. I think that the way the amp was mounted in the car allowed for it (the amp) to vibrate at certian speeds (of the car) (Natural frequency and its overtones.) (There's some physics for you.) It could be the same problem, but mabey something completely different. I don't know if there are any hidden amps on the 01 LL Bean.

 

I posted this in a different thread, where you made this same comment. I moved it over here, hoping it might help.