As some of you may recall I posted a while back about having voltage problems after I bought a rebuilt alternator. Well I traded that one in and got a OEM Mopar replacement and I am still dropping down to 12.6 volts????? WTF. What could it be. I have the afx but it hasn't done this with the original alternator.

Get your battery tested at an autoparts store.

I just got it, its an optima red top. I'll check it at work tomorrow though.

Not trying to say you don't know what your doing, but is the nut on the back of the alternator nice and tight? The guy I work with left one loose and it wouldn't charge the battery for sh^%. He is a 53 year old tech who has been working on cars his whole life, and he mest that up. I'm sure its tight because u traded it out with the mopar unit, but it wouldn't hurt to check. Peace.

check your wiring and battery terminals. Also check the fusible link for the alternator. Just because you bought an alternator doesnt mean it works, lol. Ive changed new ones out because something was wrong with them soooo many times, its really not that uncommon. get it bench tested if you decide to pull it out. also check your belt tension. Does the B+ terminal on the alternator have battery voltage? is your battery light on in the dash?

Yeah the bolt is nice and tight without over doing it. I check the fuseable link when I was putting the mopar one in. The fuse is not busted and I am getting good connections at the jucntion box? I thought about pin tension as well and put some stabilant(sp?) on it and it still didn't help. It only does it when I have my regular lights on and I put on the brakes and the cooling fan turns on!? I haven't had a chance to check the battery but I tested it when I took off the second alt., it was good then and that was only 2 weeks ago.

You have a bad connection somewhere. Do a load drop test on the Batt cables and alternator cable.

Terry

Make sure the wires are tight inside the connector, ive seen these corrode and flake apart.. unless you have a short to ground somewhere i would say test every wire for resistance if you cant figure it out