Flickering battery light

[OregonStroker]

Drove to the coffee shop this morning. When I pulled into my driveway when I got home I noticed the battery light was flickering. Grabbed my multi meter and checked the posts while running. The alternator is only putting out 12.5 Volts at idle. Shouldnt it be around 14? When the truck is off, the battery posts measure 12.3-12.4 so Im assuming the batteries are fine. Any help would be appreciated. Im pretty sure its the alternator, but want to make sure before spending 175 bucks....

thanks

[Tyler]

You should see 14.3 ish numbers. I'd have the alt tested asap.

[colekym]

I had the same thing happen to me. A new alternator fixed the problem. The only thing the battery light reacts to is the voltage from the alternator which should be in the 14.3 range like Tyler said.

[SCUFFY828]

alternator

[burmad69]

Dont rush into buying a new alt. yet check the wiring connections first at our dealership we replace them quite often

[OregonStroker]

ya ive tested everything, the connections are still shiny clean from the last time I cleaned them up and coated them in anti-bacterial ointment. I used the battery ground (as a ground) and used the charge post coming out of the back of the alternator to see what its producing. (it should show the same on the posts either way I know...) and I can only get 12.88 at idle with nothing on. It holds at 12 with every thing turned on. So it is obviously the alternator. Bumber.... they are kinda spendy.

[symbols]

If it's an aftermarket sometimes they will do that. Mine did that for over a year before I replaced it. For whatever reason the only alts that are trouble free for our trucks is the OEM

[Tyler]

Just have it rebuilt, its cheaper than brand new.

Symbols has a point. I put an aftermarket one on mine, and it chewered up two alts in 5 months. So I bought a brand new one from FORD for $400. Never a single problem.

[OregonStroker]

i hear the one napa sells is pretty solid.

[Tyler]

NAPA has good stuff. Check it out.