OK guys now i need some ideas. It's getting louder. It ONLY makes the sound in 4th gear. It's very faint but obvious enough to notice and bother you. It's not extremely high pitched... I just describe it as a whirring noise. If I let off the gas the noise stops. If I shift into third the noise stops. It is loudest between 76 and 82 MPH. All I can think of right now is the differential or transmission. Leaning towards tranny but really hoping it isn't. Anyone have any clue? Ask questions if you have them, and I'll answer.
