I decided it was time to clean up the battery box and get rid of the flooded, lead-acid, 6v house batteries that came with the coach when I purchased it 2-1/2 yrs. ago!
I don't do much boondocking so, that wasn't my motivating factor...What pushed me over the top was the never ending maintenance needed to keep the flooded batteries topped off and the leaking acid continually working on corroding the bottom of the metal battery box making a nasty mess! Luckily, after removing all of the batteries and inspecting the battery box I found only surface rust and absolutely no acid damage!
The last project I worked used a lot of AGM batteries in their remote locations. As a matter of "preventive" maintenance, I found out that they got changed out on a pretty regular basis whether they were found to be bad or not. I was able to acquire 4 good 110ah agm batteries and since I was home between projects I decided now was a good time to tackle this project and get rid of those nasty flooded batteries!
First, I took a picture of the old wiring setup just to make sure that I was able to put the cables back into position if I needed to bail out of the project before making the change!
I removed all of the old cables and lead acid house 6v batteries. I removed the chassis batteries which were already sealed agm type batteries. I washed & cleaned the new house agm's and old chassis agm's. The new house batteries were wider than the old 6v batteries so, I had to grind off the old battery old down parts that were welded to the bottom of the battery tray. I decided since the spacing between the batteries was going to be reduced that I wouldn't need to install any new battery hold downs.
I washed & de-greased the white side walls, wire brushed as much of the rust out of the bottom of the battery box as I possible. I then painted it with a rust reformer which turns rust into a black oxide primer. I then painted it with some black epoxy and laid a 1/4" thick rubber pad down into the bottom of the box.
I installed the chassis batteries and re-used the existing battery cables after cleaning and de-greasing them to make them look new. I had some 4/0 welding cable left over from another project so, I ordered some 1-hole electrical compression lugs and a cheap hydraulic cable crimper from Amazon. I also ordered some high quality glue-infused red & black heat shrink tubing to complete the new cabling between the new 12V AGM house batteries.
The old 6v house batteries were wired in "series/parallel" providing 12V to the coach...the new batteries were much easier to re-wire since they were straight parallel giving the coach the required 12V but giving me a much better amp hour capacity...Most of all, it gave me a clean, maintenance free setup!