hey folks,

I recently purchased a 2003 F250 Diesel 6.0 Super Duty.. I drove it for 2 days without any issues at all and suddenly yesterday morning when I went to start the truck, I got nothing but a repeated clicking sound.

When I boosted it, it started up, but the truck shut down 30 seconds after removing the cables.

I charged the truck batteries all last night and it started up no problem today.. I have had it running for almost 2 hours straight now with no problem.

I used a small multi meter and the batteries read 12.3V each, and the alternator is also reading the same numbers.

What could be the issue here? Is my alternator bad?

 

way to test you alternator. Turn on the truck check alternator, it should read between 13.5 and 14.3 volts when idling, have someone rev the engine to 2000 rpm.
true on all the lights, radio, heater fan to full, there should be now significant drop in your reading and it should be at or above 13.5 volts at the battery. If not time to replace the alternator.
Also get your self a Chilton or Haines repair manual.

 

go to an auto parts store.. they can put a meter on the battery and test the battery's and the charging system..... most do this for FREE.

Yes, 13.5 TO 14.5 volts with the engine running..

most likely a bad alternator..

a battery by itself.(fully charged). engine OFF is 12.6 volts...

 

So if I drive the truck is the battery going to eventually die? Its been about 2.5 hours that the trucks been running without being hooked up to a charge and there is no hesitation or anything.. as I said I shut it down and started it again no issue.

What I guess I am getting at is.. should/can I drive the truck without it dying?

 

If the voltage stays at about 12V when the truck is running, then yes, eventually the battery will be drained and the truck will stop running. If the voltage goes to above 13V when running [possibly you have to get the motor running faster than idle], then the alternator is working OK.

 

The engine has been turned off for the last 5 hours and I just fired it up, batteries gave a reading of 11.3 now after it had been running for 15 minutes.

The truck goes in for a safety on Tuesday so Ill have it taken care of then.

 

You might want to hook up a charger to it after every time you use it until it's fixed.

 

Anything under 12 volts and the batteries are discharged almost fully..charge em as said or you wont make it down the street.

 

Since you have a 6.0l I would be very careful with low voltage. They have some expensive and tempremental electronics. Make sure you batteries, alternator and FICM are all up to par.

Check out the 6.0l section linked below.
6.0L Power Stroke Diesel - Ford Truck Enthusiasts Forums

 

Do the test with the multimeter, no need to drive the truck it takes a few seconds to figure it out.
Driving/starting the truck with low voltage will Screw up your FICM it will cost you in the hundreds to get it fixed.
Do the test or pay up your choice.