1974 580 B Steering Problem

The steering got tight to where it took everything I had to turn the steering wheel while in motion. And it is still very tight when moving. In the past when it started to get tight I would top up the steering fluid and all would be good. Three days ago this didn't do any good. I first changed the filter. Still very difficult to turn the wheels while stationary or moving. If I lower the bucket to lift the front tires the steering wheel turned freely. Today I replaced the power steering pump. Still difficult to turn the wheel when stationary or moving. When I put the bucket down to lift the front tires I can turn the wheel but it is now not as easy as it was before the pump replacement.

The steering cylinders have always leaked a bit since I bought it in 2007. Yes, the king pins are a bit sloppy and the bushings are sloppy where the cylinder rod attaches to the wheel assembly but I seriously doubt any of this is the issue. Any input will be welcomed. Thanks.

1974 580 B Steering Problem