First gen overcharging.

[rjk440]

1991 D250 overcharging 18 volts.Tried new regulator and it lasted one day.Any ideas.Thanks Darrell.

 

[ENafziger]

Did you try a genuine Mopar regulator, and run a ground wire from the alternator to the regulator, and the regulator to the battery? That fixed it for me.

 

[JLEONARD]

Don't drive it until you fix it. 18 V will burn things up.