Exhuast Noise @ 55 MPH .....
, if anyone could help I would appreciate it! If it's exhaust related it would probably show up at the same rpm range in a lower gear and lower mph.
This whistling sound tends to surface when I maintain a steady speed of 40 to 55 MPH at higher gears (i.e. 4th and higher) with light throttle for a period of time. The whistling tends to die down once I step on the throttle but will come back once I start to let off. I've noticed that the only way to get it to stop is to let off the throttle for some time switch to a lower gear. What could be the cause of this annoying
sound??? 

