Gary..If you are sure there is no problem with linkage---it sounds like an
internal problem--pilot bearing failure won't cause just a 2nd/4th problem.
You might try Redline mt90 oil....may make it all better for a while. Iv'e
seen some problems go away for as much as a year before they got really bad
just by changing oil...But..you might want to put some $$$ aside for the
inevitable rebuild.
Daryl of AA Transaxle
aatransaxle.com