techrep

iTrader: (1)

Should be 14+ vdc while at idle... not rev. You need a new alt.. the voltage regulator in it is shot..

05F1504x4

Is there anything I should rule out other than the grounds for the alternator before I go buy a new one $212.

Should I check the visible link? And if so how.
Just wanna make sure

techrep

iTrader: (1)

You have checked everything I would have checked.. you could read vdc straight off the alt.

05F1504x4

Would the alternator pass if the regulator is bad because its just not under a load during the testing?

05F1504x4

Here is another thing that the truck is doing.
Idling at 12ish. Battery Light comes on.
When you rev it battery light goes off BUT the Voltage at the battery stays the same. Doesn't change at all.

Dusty Crigger

To question you asked prior yes it is likely that itd check good off the truck.

belt could be slipping too. Check that

05F1504x4

Why would the battery light go off when it's revved, but the voltage not change at the battery?

Battery gauge on the dash stays in the middle with no change as well

digitaltrucker

Beating a dead horse here. I asked backed on post 19, is this a Ford alt or a third party?

There are known issues with 3rd party alts on some of these trucks. Buy a Ford remanufactured and get back to life or take to a dealer.

I know you are trying to save money, but at this point.......................

Dusty Crigger

My best answer is that whats going on is you are getting little quick dips in your voltage at idle and your truck knows this so its throwing the light. They are probably too sporadic and quick for you to notice them on the meter if its even picking those valleys up....YET. Im afraid its your alternator in the very beginning stages of dying out. Its something I have seen them do when they first start going.

05F1504x4

Okay I'll just bite the bullet and get an alternator.