I checked the batteries and they tested good. my truck is losing charge every 3 days. i was wondering if anybody has any ideas of what it may be.

 

Welcome to DF, In the future please post your questions about your 2007 Ram in the 3rd gen ram section. I'm sure you'll get lots of help over there. I'll move this thread for you. ANd please read the posting rules. Thanks

 

Something is drawing current when it shouldn't be. Remove the positive battery cable and connect a amp meter between the battery + and the the cable. Note the current draw (should be .25A, I think). Pull fuses 'til the extra draw goes away. It would have to be a pretty significant draw to kill both batteries.

 

Do you have anything aftermarket?? Remote starter maybe? I know my bypass module draws ALOT of current even in standby mode. My truck will be dead if I let it set for 3 weeks. I have to start it every other week in the winter to keep charge.
You can have your truck scanned for Active DTC codes. A standardized scantool won't pick these up, atleast mine doesn't. I have to use my Tuner to read them. This will tell you if you have any shorts such as High current situations.

BATTERY DRAW TESTING