Batteries Lead Acid vs AGM

For me, much of this depended on battery bank accessibility. My battery bank is not very accessible and does not pull out. My coach came OEM equipped with 2 8D GEL batteries. When they had almost died, I looked at the different options, GEL, AGM and wet cells. The AGM (Deka 8D) won out because their charging requirements were almost comparable with wet cells, and they did not require the regular maintenance of wet cells. My chassis batteries are now sealed VRLA wet cells. It came OEM equipped with AGM Optima batteries. It was just a matter of switching the charger over to the AGM/wet cell function and off the GEL position. I love the ability to dry park and not have to charge up the next morning. My old GELs would not get me through the night when operating the heater. Now I can get through two nights easily while operating the furnace and my cpac and lights and even use the computer. And my alternator is not set up like a truck's alternator. It has a 4th wire, a sensing circuit wire.

Here is a really good read about GEL, AGM, and wet cell batteries: http://www.dekabatteries.com/assets/base/1927.pdf