6.0 battery volt problem 06 6.0

fdny2536 · Nov 30, 2016

Hi everyone, i have a 2006 6.0 with dual alt option, and a livewire tc on board. When i start the truck im only showing 11.5-12 volts, and after a min it goes to 13- 13.4. If i stop and restart the truck same thing happens. I just installed 2 new red top gel batteries and they have so much more cranking power than my last 2.
Is this normal? Do i have to change 2 altenators? Or is there a module i have to change?
Thank you for your time guys
John

sootie · Nov 30, 2016

whats the problem?

Strokersace · Nov 30, 2016

John, you've never owned a diesel before, have you?

What you're seeing is a drop in voltage when the glow plug relay/module is active. Once it shuts off, the voltage goes back up to normal.