I have a 2004 f-150 was driveing on highway and battery died lost all power jumped with wifes car and ran for few minutes then voltage got really really low so turned off went into napa got new battery truck started right up but my battery not running reads 12.05 volts not running when running it reads 11.75 volts across battery terminal and battery light still coming on but should i get a new altinator or is this normal for my truck please help.ty nate..

 

when ever ur car or truck is running and looses power its ur alternator.. when the vehicle is running ur battery isnt doin anything (unless ur alternator or u got a massive subs and the alternator cant keep up)...

replace alternator and you should be good to go after that.

 

Your battery light (indicator) is ON b/c the alternator is NOT charging.