I have a '99 5.4, this past December I replaced the original alternator at 130K. The first really cold day in January I noticed the rebuilt unit was making a growling noise that I took to be failing bearings. The noise got worse over the next week and I pulled the unit off, the pulle did not spin freely so I returned for a warrenty replacement.

I bought the unit at a NAPA store so I was hoping the quality is better then the other retail stores.

This past weekend the second began making the same noise, with only 2K miles. again I pulled it and the pully did not turn freely and the shaft had a great deal of horizontal play.

I'm now on the third alternator, and I checked the aligment on this installation and the pull and belt is aligned with the waterpump, etc.

could the tension assembly be putting too much downward pressure on this pulley?

has anyone had similar issues?

thanks.

 

NO it just sounds like really crappy alts. so i would say to just buy a motorcraft alt and stick it in and see what happens. I think there is a mototrcraft one? Mabey check with the dealer. HTH

 

Try a new alternator this time. I replaced the original alternator on our Jeep ZJ, and it had a bad bearing right away. The replacement for it has been fine ever since, and that was well over two years ago.

 

Hopefully you can ask for your money back, third time round - I suppose it's worth checking the tension isn't too much - don't know the routine for your model...but yeah, try a different brand of recon or new one....