On Monday I took my alternator into the local shop and he called me yesterday to tell me it was just worn out. He showed me this morning the brushes were virtually gone and the slip rings were worn down almost 1/8” (radius). Why I didn't take photos I don't know, other than I really needed to be on my way to work after just buying a new one from him.

 

I asked him it he thought it could be the OEM unit, and he said almost certainly. Not bad life at 346k miles! I put the last +70k miles on it.  SURELY at some point it was rebuilt, or maybe someone swapped in a unit from a salvage truck; the little plastic cover has the Chrysler symbol on it.

5 hours ago, LorenS said:

SURELY at some point it was rebuilt, or maybe someone swapped in a unit from a salvage truck;

 

 Quite possible, however on the other hand, I am still running my OEM Bosch alternator with two brush kits and one set of bearings that I installed myself.  Currently the alternator has logged 362,000 miles.  Still on the original diodes.

 

- John

 As long as there isn't a catastrophic failure they should last quite a while. Catch stuff before it goes critical. Especially bearings. 

 That's awesome if you got over 300k out of one. Hope they all last that long.

I started out with a Bosch alternator from factory. Now after the first failure back at around 200k miles I replaced with ND alternators either alternator will hold up as long as the W-T ground wire mod is done. Without the W-T either Bosch or ND alternator will fail and typically take either the brushes, slip rings and/or the diodes out. After that I've had good luck with both ND and Bosch alternators.