I know there's been complaints of a jerky 3pt on the L3800 tractors and as far as I can remember it was just a jerky motion on the lift not the entire tractor. Maybe do a search on the threads for a Jerky 3pt on the L3800 and see what you find. I think alot of the L38's went back to the dealer for a service recall.
Was more with the L3400 and less with the L3800. The jerky hitch can be found in all basic L models, but just a small percentage of the total number of machines out there. And only jerky when the 3 pt-hitch is raised very slowly. Some can live with it, some can't, some machine are also worst than others. It can be adjusted, but not all dealers are up to the task.
Northman, it's not a problem, just a condition and wouldn't stop me from buying the tractor.