When was the last time the drive belts were changed? This is the first thing I would be checking. While checking the belts on a 13 year old unit, I would also be looking at all pulleys, drive and idler, to make they sure they are not worn and bearings are in good condition.
Are the idler arms providing the proper tension on the belt? Did the problem start after you serviced the drive system? Did you use an OEM belt or a aftermarket one that says it fits your unit?
A neighbor has told me there is too much slack in the control arms. That is the next thing I plan to work on, because it definitely needs attention. Another person has suggested checking/changing the hydraulic oil.
Thanks for the response. I hope to get a chance to work on it later this week.
