My brother-in-law and I with adjoining properties have co-owned a Ford 4000 diesel tractor for many years. We probably put 300-400 hours per year on it. It is excellent in most respects. We repaired a crack block a few years back (electrolysis), and we regularly have to replace the PTO external bearings, as the shaft pulls out about once per year.
Don't know why, first time, we thought I was running too low rpms for the job. 2nd time, a hitch pun on the three-point came off, so that was easy to figure. Third time, we surmised our cutting job was just too much. Last year, who knows why? We have a one-ton front loader, but no rear-end hydraulics. The diesel power is sweet, and our Ford is tough!