Come on people read the post. Let me get on my soap box, and I don't mean to offend anyone. The poster said he could get 4 days before his last outing which only got him a day and a half. Something changed!!! The problem is what changed? It's not more capacity, or crappy batteries from the factory, or several other of the guesses/suggestions that have been posted. I took his post to mean why couldn't he get 4 days like before? Yes you can throw all the mods and money you want to and increase his dry camping time, but if he has a bad converter, a light left or a radio left on, or any other of many possibilities, you haven't fixed the problem. I'll get down now.
By the way, my camper didn't ship with a battery, and I doubt any of them do. The dealer installs the battery when the unit sells, or at least that's the way it is at most dealers I've checked. That's why some get Interstate, some get Exide, some get .... It would be useless to ship a trailer to a dealer with a battery in it when the trailer might not sell for a year or more. Detectors would kill the battery before the camper sold and the dealer would have to replace it under warranty first thing. Now I'll leave.
2012 Ford F250 ext. Cab 4x4
2002 Jeep Wrangler Sahara
2008 Yamaha V-Star 650 Classic
2008 Work and Play 18LT