Was hoping you might be able to point me in the right direction... have a 1998 F250 Triton V8 original battery etc. Everything has been working fine, then on a short trip (approx 8 miles) truck started fine, 3 or 4 miles down the road I notice the power windows just stopped when I hit the up button, then notice the battery gauge was reading really low (around 8), turned around headed back and noticed the instrument panel went out all gauges reading as if truck was off, the needles bounced a few times then nothing again. Another mile down the road after slowing down and turning (turn signals did not work) the truck acted like it did not have get up and go (it is an automatic) when you hit the gas. Reminded me of the way a truck acts when you try to take off in second gear in a manual. Did not have radio or A/C or heat etc on. Got home and stopped in driveway and before i could put it in park, the truck died. Put in park, turned key off and tried to start it and nothing... couple hours later it tried to start but didn't, put on battery charger, later fired up just fine. Battery gauge was reading half way between 8 and 18. Let it run for about 45 minutes... battery gauge a little above half way...gave it a day and fired it up again and let it run, battery gauge a little under halfway.... gave it a couple of days , yesterday fired it up fine and after 30 minutes of running I went to shut it off and the battery gauge was low (near 8!!) Tried to start it today and would not start. I am just trying to keep truck running since it will be sitting for an extended period of time while owner is deployed in middle east. Reading through past posts I was going to test the battery with mutimeter when on and when off. Any other suggestions that come to mind that might be obvious? Do you think I am doing any harm to the truck by charging the battery and just letting it run? I was going to fully charge the battery and then disconnect the cables while it sits so battery will quit discharging. Any thoughts?

 

It sounds like the alternator or regulator (which is usually inside the alternator). If you want to take it off and run to Advanced or Oreilly's or whatever and have it tested, I think you will find that it isn't charging the battery.

 

Oh ya it is a 98. I would have the battery checked as well.

 

Have the battery checked. A '98 vehicle with the original battery is about 2+ years into running on luck with with a 7 year old battery.