When I replaced my F-150 alternator, I kept my motorcraft to rebuild at the time, because I expect I'll need it again one day. I intended to drive my truck another 100k+ . Already got about another 70k on it. I'll probably swap it proactively at some point when I put another battery in it. Sometimes it's failed batteries that kill the regulator in alternators, for best life start a new alternator with a new battery.

 

That's not a bad idea. One of my alternators is one that I actually rebuilt.... it was the original in my Expy, and it had a dry front bearing in it. I used the Victory Lap kit on it.

 

Why not pick up a junkyard 130A unit, rebuild it, and install that? Then you could rebuild the original and keep it on the shelf as a spare (or just shelve it as-is, since it still works).

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