I need new house batteries

[Ted Couch]

We have a 1989 40 foot Marquis and I am wondering what house batteries you are all using. The golf cart batteries are too tall to fit on the tray. I don't know whether to go with sealed or water add. Optimum brand? Costco? I appreciate your input.

[Richard Davis]

I just recently replaced my house batteries with new AGM batteries from VMAX.  Make sure they are true deep-cycle batteries.  Since the tall GC2 size batteries will not fit in your battery tray, look at Group 24 or Group 31 sizes to see which will fit the best.  Flooded batteries are the cheapest, but personally I cannot tolerate the corrosion they cause and the maintenance they require.  Lithium Iron Phosphate are the best, but also the most expensive.  And, most likely not compatible with any of the charging systems in your coach.  Having said all that, my recommendation would certainly be the maintenance-free AGM batteries in whatever size will fit your battery tray.  Be cautious of the Marine-RV batteries sold by most retail stores (Walmart).  They are not true deep-cycle batteries and will not last in your application.
Richard   

[Keith Moffett]

Deka makes good batteries. 
When it comes to Interstate, go  Deka.

[Joel Ashley]

I’m surprised GC2 standards are too tall.  The Interstates in our coach lasted 12 years, basically charged by solar while parked by the house here, often for years without moving. But I too got tired of the corrosion, and replaced them with AGMs.  Lithiums were too expensive and required $$$ in component changes aside from the batteries themselves. 

But the inverter and solar system hasn’t played that great with AGMs.  The Magnum inverter remote is just barely configured for handling them, and had to be set differently.  Ever since then the remote would come up with unusual readouts.  I had to get Magnum help several times, and it still behaved erattically.  The solar controller was not built as per its manufacturer’s documents, so resetting it for AGMs was a headache to determine, and I’m not certain I ever got that right.  It wasn’t really made for AGMs apparently.  I intended, if we could just get back on the road again, to have an updated solar system installed.  A new inverter remote would help too. 

Your older coach may or may not encounter similar issues with AGMs.  I can say that indeed there is no corrosion problems anymore, and of course no rewatering hassles.  But I’d still check your infrastructure compatibility first.  You may still opt for wet cells.  A straight up, tit-for-tat replacement  proffers the least headaches.  I myself  would’ve otherwise got the GC2s at Costco, the best deal on Interstates, considering I got 12 years out the original Interstates.

Joel