I have a C500-YS100 lift that has a wander problem with the steering.
When operating this machine, the steering functions properly when maneuvering in and out of loads for the most part but seems to be progressively getting worse over time.

The problem starts up when cranking the wheel all the way from one side to the other. It seems like you actually turn the steering wheel one or two extra revolutions once the steer-axel wheels pass through the centered straight position. It's mostly noticed when turning at a fairly fast rate. It's not noticed as much when turning the wheel at a slower pace.

Also, when driving the machine straight (across our yard) you do have to compensate the steering sometimes because the machine tends to turn itself to the left or right. This is something that has progressively gotten worse over the past couple years. Years ago it really wasn't a problem and it was only noticed during extreme steering revolutions.

Now to rule out several things. All tie rod ends have been checked out or replaced. The primary tie rod link from the steering cylinder has been re-adjusted and the ball stud replaced. Also, the pivot link at the front of the steer cylinder has also been replaced. King pins and the center pivot bearing between the two steer wheels are also in good shape.

My thoughts are that this could be more of a hydraulic problem perhaps? Maybe the steering cylinder needs to be repacked? Or, perhaps a worn packing and cylinder bore?

Or, perhaps the steering box at the bottom of the steering column where the hydro hoses tie in could have something worn? (That steering box is something I'm not really familiar with on this machine.)
I would tend to think that if that were the problem though, it would be noticable in tight meneuver situations which leads me back to thinking the steer cylinder would be the culprit.
Yes / No?

What do you guy's think?

Sorry about the long posting. Hope I didn't confuse anyone.

Thanks in advance for any help.

Jake