Alternator failure or something else?

[scjmc]

Thanks for all those replies. I just wanted to update: Problem Solved! I had problems with the new alternator I used being defective from the factory (thanks NAPA). I got another one and now my charging system problems are fixed!

 

[scjmc]

Dont buy NAPA alternators. I need alternator #4 (NAPA #3) now.

 

[1LoudLS]

damn, usually napa parts are pretty good. are you running any power hungry aftermarket equipment, or it it pretty much stock

 

[scjmc]

damn, usually napa parts are pretty good. are you running any power hungry aftermarket equipment, or it it pretty much stock

Well..... I do have a 15 with a 1200 watt amp. I have a 2 farad cap however. I havent made any other high power modifications like electric fans. I drive mostly highway too, so the battery does not suffer from many short trips. If I can get NAPA to just give me my money back I will buy Motorcraft. Another note about NAPA the store I bought the NAPA brand alternator from is the only one that will warranty it. My more local NAPA store will not.