My girlfriend’s Elantra (mid 90s model, I think) makes an intermittent noise when on the highway. It sounds to me like it could either be from friction or some sort of wind noise, but I suspect it’s the former. It only seems to happen at speeds above 50 or so. When it occurs, it is always the same pitch and loudness – these don’t seem to vary. It’s rather loud, to the point where it is pretty unpleasant to drive when this is going on. It has happened both when my foot is on and off the gas pedal. When the noise happens, it can last anywhere from just a second to up to a minute or more. I haven’t been able to identify anything obvious that it’s correlated with – wind direction, grade of road, etc. The only thing I do know is that it only seems to happen at highway speeds. We never hear it during city driving.
So far one mechanic has confidently misdiagnosed the problem as a bad wheel bearing. Any thoughts on what could be going would be much appreciated!