I have a volvo 240 gl 1991, and when i drive at a speed of 60kmh to 80 kmh (most noticeble in 4th gear however also happens in 3rd and 5th) and let go of the gas pedal it makes a weird high pitched chirping noise, hard to explain the sound, it i press the gas pedal again it goes away, what could that possibly be?
My car has a manual transmission.
Without additional information it would be tough to say, however based on what you are describing, it sounds like potentially low differential oil causing the gears to whine a bit. There are also what is called trailing arm bushings which support the rear end and when these are worn, this can cause the rear end to move slightly more than normal which could also possibly make this kind of a sound. I would recommend having an expert from YourMechanic come to your home to diagnose the noise firsthand and help you repair it.
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