I picked up a 1992 H35XL LP. Seemed to be in pretty good condition but known issue didn't go forward and backwards. Guy said it had a monotrol issue. Figured it might be an easy issue so I took a gamble and brought it home. I quickly found a switch in the monotrol pedal that was bad so I replaced that harness. Turned it on and went back and forth real quick seemed like it was going to work. A few hours later I get in it and go forward a foot and then nothing. No forwards or backwards. Eventually I had it running and tried pushing it forward and you can hear some grumbling type of noise from maybe the front drive unit as well as noticeable vibration. I turned it off and then tried pushing it forward again by hand. I hear a click from the front drive unit. Start it up again and starts going forward without any extra noises. Did that for about 4 feet then nothing again. After that it was more of the same grumbling noises from the front drive unit area. Any ideas? Thanks for any help!