Replacing two 6 volt house batteries with one 12 volt

Honest question--I don't know---can a single 12 house as the Aux, start the Diesel engine, which now has two 12s for it, if those two 12s are dead?

X3 can,t beat wal mart, theres one on evvery corner.

midnightsadie wrote:
go get a wal mart deep cycle marine battery biggest that will fit. been using them for years no problem.mine are four years old last month.

X2 Mine usually last 4-5 years and are reasonably priced and easy to find.

Any size agm or sealed battery.

Buy the biggest standard battery that will fit. IMHO the RV/Marine dual purpose batteries are a waste of money.

Just make sure it is fully charged when you put it in storage.

Rather than have 2 12V grp 24 or 27 batteries I went with a single AGM 4D. It produces about the same amperage as 2 6Vs but eliminates the 2 extra possible problem creating connections.

It is heavy, about 115lbs, but being no maintenance & having a lifespan of at least 8 years I can deal with the installation challenges.

wa8yxm wrote:
Since you no longer dry camp it should work just fine
The big advantage to the pair of 6V=GC-2 is capacity (220 AH give or take and half usable) this compares to one 12 at
Group 24 75 ah
Groups 27/29 just under/over 100 AH
Group 31 about 130 ah And only about 1/4th usable.

So that's the only major difference.

Not relevant to the OP as he doesn't need a lot of amp-hr.

But 6V Golf Cart batteries are true deep cycle batteries and will hold up much better to regular discharges down to 50%.

Other than a few hard to find specialty batteries, pretty much anything you find in 12V is really a starting battery that won't hold up as well with deeper discharges.

They are constructed differently with deep cycle having fewer but thicker plates, so while they won't put out as many amps, they can do so for longer and can handle it without damage.

But again, if the OP isn't going to boondock, he needs enough to run the slides out which in terms of amp-hrs is nothing when you will immediately either plug into shore power or start the motor and recharge them.

An inexpensive Costco group 24 battery would do fine - about $60.

If you dont need a battery then a small lawn mower battery would work, 12 volts of course.
and of course you will need the battery at times at least for lights or when the power at CG goes out, or when pulled into a rest stop, but one 12v marine batt is also plenty.

strongly recommend getting the standard marine battery, cheapest is fine, though.

2 GC batts are ideal, but not if you will never need them

Monaramblee wrote:
08 Holiday rambler Vacationer diesel
with two 6 volt batteries for the house and two 12 volt batteries for the chassis.
I would like to replace the two 6 volt batteries with one 12 volt marine/rv battery.
We dont dry camp anymore. Any issues with this idea?

It would work, but you also might want the extra if you ever need to use the house side to assist starting the engine. Two 12s instead of two 6s?

There is also the redundancy argument for having two 12s. The gen starts off the house batts? Door steps? Slides, Jacks?