Ok I have my Summit driving me crazy. Few months ago I was doing some driving in low and the servo is always making noise. I installed a new servo and didn't have an issue for the next 5 to 6 low gear running. Now the sound is back. I haven't hit anything or done anything that may make it off. However today only thing different is I am using my other Tqi4. It is the TX that came with the truck. It don't have the iPhone control. That Tx is offline until I can figure out how to fix it. An update messed that up today.
Just took the link off and the sound stays. However if I change the thing while the link rod is off the sound isn't there when moved back to low from high. However replacing the rod and shift and driving it comes back. Even after the rod is removed until it is shifted. Makes no sense to me.
So are you saying that you can remove the link when it IS buzzing and even when the pressure is released it still buzzes until you make another movement?
Sounds like the servo isn't completely meeting its desired end point. I don't know whether you adjusted anything when you put the new servo in but it could be that the link is not allowing the servo reach its end point and that's what the buzz is.
To adjust you pop off the little plastic piece that clips onto the servo horn and it can wind up and down the thread on the link. The other thing that can happen is the servo horn goes around far enough that the whole link setup hits against the horn again not letting it reach end points. In this situation you have to take the servo horn off and move it around a bit.
Summit; Spartan; Others yet to come