My son who is 1,000 miles away called me and told me that his '96 4.9 truck just died on him and he coasted into an Advance Auto Parts store. They told him that his battery was shot and they sold him a new one. He said that his charging guage needle on the dash is not in the middle where it normally was and that it is only a quarter of the way over from the left. I'm thinking that the alternator is bad and that for now the truck is running just on battery power and that's the reason the guage is not reading normally. Am I correct on this? Also could the voltage regulator be causing this? Thanks for any suggestions.

 

I would say the alt is shot as far as regulator could be that or rotor or the diode pack.

 

the altermcnator

 

start it, disconnect the battery. what happens ?

 

Probably the alt, but no need to spend alot and replace it, 99% of the time the brushes are shot. Standard ignition or bwd from adv auto sells the brushes for under $15.00. My last two alts I changed the brushes and it did the trick.