GM Alternator question

[nismou20]

My battery is low on charge, and my GM alternator is acting wonky. I have a ground strap between block, chassis, alternator, and battery. When checking Battery ground to alternator ground I’m seeing 5-6vdc. Should be 0. Do I have a internally shorted alternator? Hot terminal of alternator to battery ground also shows 5-6 Vdc too. At times it seems to charge ok at 13-14vdc. It’s erratic. Are GM alts known to go bad like this?

[23yrRebuild]

I've had mine for years, and it's still going strong. If I were you, I would remove it and take it to your FLAP to have it tested. And while you're at it, you might as well remove your battery, put a full charge on it, and have it load tested, too...

[redroadster]

Ground strap ? As in braided ribbon style , those were not great run a redundant cable neg cable to the alt area or block to see if that fixed the low volts DC power moves neg to positive
13 to 14.4 volts is normal lower when the amp load is big ,high when lits ow
I'd check milli amp draw on alt , with key out of ign no other draw
14 to 25-29 is normal with 1 wire types. if you do not drive a car / alt much the brushes comintator can glaze / tarnish over and loose good contact . auto parts have an
electrical IC tester, usually free