What Is Leaking Grease/lube On My 1997 Ford F150 4X4

The truck has 86,000 miles, clean and nice.

Front end on 4X4….. There is grease wetness on a front wheel. There is like a small power transfer shaft between the front differential and the component which holds the wheel (I will call that component a wheel bracket) The wheel bracket has the ball joints fastened to it which allows the wheels to steer the truck. I can not see any leakage at the seal on the differential nor on the inside of that wheel bracket. The only grease seepage is on the spoke wheel rim.

There was brake work done about 5,000 miles earlier, where the rotors had to get beaten off… They were absolutely stuck/rotted in place. The mechanic had cut/ground slots down into the rotor and output shaft (where the wheel studs are fastened).

The mechanic put anti seize between the rotor and output shaft and some of it had been spinning out and smoking the breaks a bit, but there was a lot of time between that and this grease wetness showing up now.

Thanks.
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