modded 06 truck, 33k miles, just put in brand new batteries and it keeps boiling the passenger side battery and draining the driver side battery. I had the alternator checked and they said it was fine, anyone have any other ideas? I check most of the ground cables I could find and they are good

 

Why did you have to change the original batteries so quickly? If you were having a problem with the past set you might need to get the ECM checked. I believe the voltage regulator is built in to the ECM.

 

well I dont want the battery to blow up and destroy the paint on the fender and I try to avoid the dealership the truck is modded, but thats where its going to get the flash sometime this week I guess

 

You have a loose and/or corroded connection to the driver's side battery.

https://www.dieseltruckresource.com/...0-t246830.html

 

thair is a battery temp sensor under the battery that tells the truck how hard to charg. when it dies it over charges till the battery boils because the truck doesent know the battery gettin hot. I think it under the driver side but it usally boils the passenger side. good luck.

 

should have stopped right there. The rest is juuuuuuuussssst a bit outside!