Truck beeps then stalls and restarts after it cools

[MotherPrometheus]

So I'm at a total loss. May need some help with this one...
I have a 2004 V8 Sport and yesterday It beeped at me a few times then stalled out. After a few minutes it started just to go a couple miles, beep a few times and stall out again. each time I start it up and it stalls, it takes longer to restart and stalls sooner. No lights coming on the dashboard....HELP

I took it for a drive today after work and it started beeping only three blocks in. As I was pulling into my driveway it just kept beeping

 

[MotherPrometheus]

Update

So after further testing, it appears to be either a bad battery or bad alternator. I jump started it and it ran fine with the cables connected. Once I disconnect the cables it started beeping within minutes and shut off again.

 

[waypoint]

So after further testing, it appears to be either a bad battery or bad alternator. I jump started it and it ran fine with the cables connected. Once I disconnect the cables it started beeping within minutes and shut off again.

Good diagnostic step. Whip out your volt meter and probe the battery pos and neg terminals with the engine idling, no jumper cables. Should be > 13VDC. Anything lower is likely a failed alternator.

Unless you're in a big rush, RockAuto carries Denso rebuilt alternators with a good history of reliability. Otherwise I'd have your current one rebuilt at an automotive electrical shop if there's one locally. Or roll the dice with a parts store rebuild...I've had good outcomes with NAPA alternators in other vehicles.

 

[AuSeeker]

Good diagnostic step. Whip out your volt meter and probe the battery pos and neg terminals with the engine idling, no jumper cables. Should be > 13VDC. Anything lower is likely a failed alternator.

Unless you're in a big rush, RockAuto carries Denso rebuilt alternators with a good history of reliability. Otherwise I'd have your current one rebuilt at an automotive electrical shop if there's one locally. Or roll the dice with a parts store rebuild...I've had good outcomes with NAPA alternators in other vehicles.

NAPA also sells the reman. Denso alternators, they're about $20 higher than Rockauto but after shipping it could be almost the same.

If you get a Denso from NAPA you may want to call first to see if they have one in stock, if they don't they usually can get it there within 24 hrs or less.

That being said the Denso only has a 12 months warranty but the NAPA Power Plus Alternator has a Limited Lifetime warranty and is $32 less than the Denso.

 

[wcjeep]

If price is close (Napa vs Rockauto) I go Napa. Returns are much easier.