Charging or Battery problems

[Raising Hell]

Whats up guys?? Got a 2006 Ford F350 dually. The battery light started flicking on and off on the dash for a few days.. So I replaced the alternator in the truck.. Didnt help.. Had Interstate batteries in it so I took them to Interstate where they were checked.. They were fine but the nice guy replaced both of them for me anyways.. Still same result. Now one time you will start the truck it will start with full twist on the starter and fire up rite away.. You can shut the truck off and open the door and the interioir lights will barely light up like the batteries are stone dead.. Truck will not even attempt to start at this point. Last night while running behind a buddy of mine he said he noticed all the lights on the truck flicking off and on and going dim then bright.. Got to be a ground issue rite??? But where do the grounds from the batteries go to on the frame?? Any other knowledge of what it could be?? Sorry for the long post just wanted to put everything out there.. Thanks for the help..

[Raising Hell]

Ohh and by the way new Alternator was tested when the battery light on the dash was on and the alternator was putting out 13.965 volts. and the batteries were at 13.79 volts. So the charging system and batteries seem to be fine.. Thanks again

[Young-SC-Owner]

Subcribed.

[JSchuricht]

You need to start eliminating some stuff with a multimeter.

Next time you are parked with the lights dimming, check the battery voltage directly from the battery posts, not the terminals. Also check voltage at the terminals, voltage from the chassis ground to the battery positive and alternator voltage.

[mikewayne]

One or two cells in your battery most have gone weak... nothing can be done you just have to replace them.... yes your ride still runs on a low battery power but its too risky!!!

[csamus]

I just had a problem with my chrarging system and replaced alternator and batteries. The problem turned out to be the ground stud on the lower front of the engine was corroded. Took it apart and cleaned it up. Starts and runs like a new truck again. Hope this helps!