Dead Again

[fordguy2]

So for the third time this summer my truck has been dead when I went out to start it. The other two times have had me replacing my alternator. So now is my question, what could be causing my batteries not to charge since I have put 2 new alternators in already? Something shorting out? Radio being on causes it to drain? Im lost and have no clue where to start and all the auto parts stores will do is just put in another alternator. If anyone has any ideas of what I can check please let me know.

[a.alford]

how old are the batteries? do you use the trucks electronics alot when its not running?

[fordguy2]

Batteries are about a month old with the first alternator then put in the second one. I use the radio all the time but how would that cause anything cause it never bothered it before?

[ianstew]

I would start by checking all grounds, and all the connections, and make sure that there is no corrosion. Have the batteries load tested individually.

[a.alford]

i would bet that there is a bad ground somewhere and the poor connection wont allow the truck to start

[Coops99SD]

Auto or stick?? Dead as in no power what so ever or you have power when tthe key is on it just won't start? Reason I ask is because my 6sp did that to my sin in law..... he thought the batteries were going bad. It ended up being the clutch safety switch, you mash the pedal to the floor acts like bad batteries. Ease the clutch out just a little it would start right up........

[7.3Excursion4x4]

Had the same problem a couple months back and ended up going through 4 new batteries and 2 alternators. Couldn't figure out why at speed the alternator was only putting out 11 volts and at idle was putting out 10.5 or so. Ended up cleaning everything and coating with battery corrosion protection spray and it ended up being the ground going to the block. Ever since, 13.5 at idle and 14.5 running. Took a few hours but worth it.
Good luck

[Tj Krawler]

When you say "dead" do you mean it just won't crank? Or the batteries are weak/dead?