2005 f250 6.0. Been running great until this weekend. Battery light came on. Couple hours later the radio went quiet but was still on and then the lights all went off and then it died. Jumped it and drove about 4 blocks and it died again. I replaced the alternator and it worked great until this morning. I shut my truck off in the drive thru and it was dead when I went to start it. I tried a few times of turning the key on and off and then it started. I made it around 6 blocks and it died. No lights or click or anything. Brought it back home and charged the batteries. It started I let it idle but it died after running for 4 or 5 minutes. PLease help. Im a dumby when it comes to electronics. Thanks

 

I will assume that your truck has only one alternator like mine does and suggest that you buy TWO new batteries. Yeah, I know, but these marvels of modern technology are very dependent on good batteries. When the batteries won't hold a charge with a new alternator, they are pretty much done.

After you get two good batteries, if the problem persists I would guess that testing the FICM (there's a sticky about how) would be the next task.

 

Yes, this is a common problem where diesel guys will buy one battery if one has a dead cell or is going out and stuff like that. But if you put a new battery into the circuit with an old battery, the old battery is going to harm that new battery and cause it to not act like a new battery at all..

Your best best is to buy two new batteries and that will more than likely fix the problem.

Sounds like you have a dead cell, coming form personal experience.

 

Well fellas I spent the day testing everything. Took my batteries and alternator in to be tested and come to find out autozone gave me a bad alternator. So hopefully this solves the problem

 

Well at least they will admit they gave you a bad alternator, hopefully the new Alt, works if not batteries my friend, or a voltage requlator if ford has one...

 

I'd rather had a bad alt or battery then having to trace a bad connection in my wiring :/

haha! but good luck on the new alt!