Case 480E LL Construction King: This tractor suffered a Belville spring failure and the whole shuttle unit was rebuilt 2 yrs ago with new clutches and the works and has been great. This spring its developed a jerky motion when idling down in gear. At idle this unit should smoothly cease movement but instead jerks and lurches to a stop. And to complicate matters it doesn't always do it. I pulled the shuttle and opened it all up again but found only a tiny fragment of a fiber seal blocking a fluid port of the input shaft. All else was spotlessly clean with no wear. I cleaned everything and replaced the seals and unit worked fine for a few hours but returned to its eratic behavior. What might be causing the problem? Mark
Is this 480E LL a 2 wheel drive? If so the park brake disc may have worn splines. Typical symptom is when coasting to a stop it gets very jerky. The disc wobbles and contacts the pads causing it to be jerky especially on a grade or slightly rough terrain. If it is a 2 wheel drive and you want to make certain this is the cause, remove the park brake and run it around, if it stops you found the problem. Sometimes new pads will help a bit. Let me know if it is 2 wheel drive...there is a fix without replacing the main shaft but it's a bit detailed. I've seen this happen with old 580E and 580K.
Thanks for the idea. The park brake has been "reengineered" to move the disk slightly. This may indeed be an issue. I'll get back when I check it out. Thanks again.