Possibly could be looking for a new alternator. While running, battery only at 13 volts. From what I can tell it’s original type alternator. I have 302 running mustang efi , newer stereo and mostly LED lights. Original wiring in truck as well. Should a 75 amp work well enough for all the accessories and not dry the original wiring?

Alternator I have now is in the pic. I have had it for 17 years (came with the bronco). So do not know how old it is.

I would think that if it's pumping out near it's advertised amps, you shouldn't have a problem. Could be your battery getting old too?

There are shops in Denver that can rebuild these and get more output from them. It was years ago when I did this sort of thing, so perhaps those businesses are no longer??

New battery and just had the alternator tested “good”. Tracking down possible other issues right now.

Really only leaves the voltage regulator doesn't it?

Mine went out on me and caused all sorts of weird issues till I figured out it.

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Well that makes sense. I mean it doesn’t have many miles on it, but it probably is 15 years old. We all know how some of this new electrical stuff works on these old trucks.

Update: swapped regulator and it went back up to 14.46 volts while idling. Went for a drive later and started acting up again. Made it home and checked and it was back down to 13volts. I must either have a bad wire somewhere, or possibly the regulator crapped out already.

Any ideas now?

Got a new alternator that was supposed to be an upgraded unit but similar to my old one. Wiring doesn’t quite line up though. Any thoughts on how I can wire this up? Or do I need to get a different alternator?

PiXD are old one, new one, wiring

Maybe @viperwolf can chime in? Bet he knows off the top of his head.

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