When I drive my car and after after going over 50Km/h (speed not distance) I start getting a chirping noise like repeatedly and doesn't stop once I've slowed down to about 45.......the car sounds perfectly fine taking off and idiling. I'm guessing it has to do with something with the Tranny???
is it a fast chirping noise, or a slow chirping noise. Does it increase in frequency when you speed up, and slow down?
Check your brakes, and CV joints would be my first suggestion, since the problem seems to be related to how fast your going, I don't think it would be an engine problem.
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-Chris