[greywolfford]

Ok got a 07 6.0 brand new batteries and alt. load tested all tested good put a new a new pig tail wiring harness to alt. replaced glow plug control box. no codes just battery light stays on. something is drawing on the batteries with key off . driving down the road for 1-1/2 with lights on ac on the truck just dies any help thanks.

 

[wvrrcarknocker]

As I posted in your other thread, try this if you have time.

 

[351fifty]

Damn, that's a great idea there

 

[wvrrcarknocker]

Though, the more I think about it, the more I think your alternator could be at fault as well. Check your battery voltage with the engine running and make sure you're getting 12.5V+. Wouldn't hurt to get both batteries load tested, and get your alternator tested.

 

[greywolfford]

The batteries and alt or brand and all.was load tested befor i installed them. could it be a bad ground i found the ground from batery to body its in good shape but the other grounds i dont know where to look