hi DannyV,
I'll suggest you try Private Messaging "1danny", he can / will be a lifesaver for a Yanmar.
I too see a Kingpin failure if I do not get off my arsh and replace the front inner wheel bearings. I foresee this happening to me. I'd bett your inner wheel bearings were shot and wore down the kingpin too failure. Dang, now I'm scared to keep cleaning up before maintenace is performed... bearings are still there but the inner bearings are wobbly as heck, the balls pop out the race and I'll be at Kingpin failure too.
EDIT: Get bearings and seals for both hubs, cheap insurance.
Good Luck
rhett