I run the 645 on my Matrix buggy for steering. I would make sure that your steering is not binding up at all on its own. My Matrix steering was binding and needed to be loosened/adjusted and that helped as I had the same problem you have. I am not convinced the 645 is ideal for what we want it to do. It is an OK servo but when you step up to an even stronger servo you will understand the difference. I went to the 5955 and that is one bad **** servo! Good luck...