Jerky at slow speeds
I have a 1992 4X4 250 Trail Boss that ran fine for the last 15 years. It just started to be jerky at low speed going forward or reverse. When I am slowing down, it starts jerking and last few inches the rear wheel leave slide marks on gravel when the back wheels lock up. When in neutral, all is fine when going downhill or uphill. When rear is jacked up, the jerking still happens when on slow idle. I have changed the back chain recently + tighten the center and front chains. No particular noices. Can anyone help?