Originally Posted by
CraigMBA
After I made my chassis brace, the driveline got a lot quieter with no other changes, so I knew what happened. But I never checked the belt like I did in pictures, and when I did I was like OMFG.
I was able to run the belt tension a lot looser and not have the belt skip. When the chassis flexes like your top pic it will pull on the rear shaft also and it changes the gear mesh. Bad for 48 pitch gears.