Front axle swivel balls, knuckle wipe seals and grease

The front solid axle's swivel balls and knuckle wipe seals are the most-inspected wear item; some black grease is considered normal and by-design (they are meant to be repacked), but yellow, watery or excessive grease signals failing seals letting water and grit into the hubs. Experienced owners caution against opening high-mileage knuckles unnecessarily and flag inner CV boots as a costly rebuild.