Engine/Transmission (1998.5 - 2002) dead batteries

[tall1]

I have something draining my batts, I leave it sit over night and the batts are really low by morning. I don't have any add-ons and the batteries are fresh. this is in my 99 truck

 

[JFaughn]

It starts with what kind of tools you have access to , need and amp gauge so you can identify how much load , it should be significant being that you have 2 new batteries and that there drawn down overnite , after finding a way to measure the draw you can pull fuses one at a time till the large draw stops , then you have it narrowed down to that circut , but you may start with some of the most comin , glove box sw. not turning lit off , same with brake peddle, very comin,