I just had to replace the lower ball joints on my 2001 Expedition at only 42,000 miles along with the seals for the front crank casing between the axles. Is this normal or did these parts wear out too fast and possibly be defective?

 

Normal !

 

how did you know they needed replaceed? what were the signs

 

Had Ball joints done at 27,000 miles

 

There was a slight noise coming from the left front wheel when driving slow....that's it. I really didn't know until I took it in for an alignment at which time the mechanic discovered it along with the bad seals on the front axle crank case.