Does anyone else have a battery drain issue,5.9L gasser ,just did and entire top end rebuild ,put in a brand new battery,it cranked over and fired up ,but had to leave (truck is not at my house) and today ehen i went back my battery only had 3 volts of power ,no lights were on or anything ,could something be draining my battery or could it be a bad battery

 

It could be either or, testing a battery can be done by an auto parts salesperson for free. Try this site for how to test for a draw: .

 

Twice I've had bad alternator drain the battery, both had failed diodes.

 

 

Entire thing to my knowledge. As the rebuild kitsch dont come with it

 

You could replace just the diodes, but what I've looked into it, doesn't seem worth of doing. New bridge rectifier isn't too expensive, alogn with brushes and bearings. Overall quite straightforward to do. But I wouldn't bother to do if the alternator is cheap aftermarket unit, they aren't that expensive to begin with. If the alt is original I would rebuild it.

 

Thanks for the info guys. I have been chasing an issue like this on a buddy's truck. His headlights will turn on randomly at night and kill the battery. I suspect a bad relay but even when the lights are not on his battery gets drained.

Alt is original. Probably time to replace or rebuild that first. Also time to get proficient with a volt meter.

 

i still have my original alt,but with almost 320k on the odometer i might be due for a replacement