Go Back   iRV2 Forums > MOTORHOME FORUMS > Class A Motorhome Discussions
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
Thread Tools Search this Thread Display Modes
Old 08-31-2015, 08:13 PM   #1
Senior Member
FIRE UP's Avatar

Join Date: Dec 2009
Location: Out there, somewhere
Posts: 5,942
8D battery as a house batt, any thoughts?

I've got this running on another forum 'cause I want as many EXPERTS opinions as I can conjure up. I thank you all for reading and, sending an answer.

Well, our Costco, 6V golf cart batteries (dated 8-11) just passed the 4 year old point and, based on a few things, I'm not sure they're holding up their end of the bargain for keeping charged and holding it. Now, I've been a pretty good one for maintenance and all that for most of my RVing life. But, I will admit, I've grown a bit complacent when it comes to my RVs batteries. It's one of those things, "out of sight-out of mind" things.

More than once, I've decided to check on them to see how things are and, I open the bay door where they're stored and, it looks like I'm cultivating GREEN FUZZ/CABBAGE at many of the terminals, YUCK!!!

It takes me a good hour or two to remove, clean every thing, including cables, cable ends and all that. Not to mention, that's very tedious job to do because if you get any of that on your cloths, you all know what it does. And, I've had to fill them several times when doing this process. In a couple of cases, they were down to around 11 volts or so.

And I don't want to hear about those multi-fill or, Auto fill gadgets because, THEY WON'T FIT. I've got right at 1/8 of an inch in clearance of the bay door frame when those batteries are slid out and back in, in their tray.

But, I always babied them back to life and, used them on trips. But, lately, it seems as though they don't have the STAMINA that they did when they were new. I hate running the generator in quite camp grounds just because I'm allowed to. But, sometimes their down to 12.0 in what seems a short time of using them. And that simply entails the use of a TV and DVD player for maybe, an hour or so. Sometimes they're higher after that time frame and, sometimes they're at that low voltage.

So, this brings me to now. I'm considering a few options here.

1. Just buy new 6V ones (4 of them at a local cost of $140.00 each plus tax)
2. Since we do mainly "hookup" camping about 60% of the time and, dry camping the rest, I might go back to 12 units 'cause that's what was in there when we purchased it four years ago. Not sure of that option yet.

And 3, I'm thinking, JUST THINKING at this point, about maybe going to an 8D battery for a single house battery. Those things have around 1150 CCA. Now, I know, nobody cares about CCA in house batteries. But, when I asked the Interstate Salesman about ampere hour capacity, which is what many Golf cart and RV house batteries are rated at, he didn't know.

I also know that, it would be the ONE and only battery while, if I kept the (4) 6 volt operation, if one went bad, I could just replace the one. Or, the same with a (3) 12V Deep cycle Marine setup.

But, I can't help thinking that you'd get this monsterous amount of time on an 8D before you'd need a re-charge. What say all you battery wizards out there in RV land???

2004 ITASCA HORIZON 36GD, 2011 GMC Sierra 1500 4x4 Toad '08 GL 1800 Gold Wing
Retired-29.5 yrs, SDFD, Ham - KI6OND
Me, Karla and the Sophie character, (mini Schnauzer)
FIRE UP is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 08-31-2015, 08:29 PM   #2
Senior Member
FunGus's Avatar
Monaco Owners Club
Join Date: Jun 2015
Posts: 371
My Country Coach had two 8D batteries for the house and one for the starting battery. They seemed adequate with the 2 of them, but I can't help but wonder if you wouldn't be a little "lacking" with just one of them. Dry camping we would get 3, maybe 4 days before they would need a charge depending on how much the furnace was running. So with just the reserve of 1 you may only be looking at a day and a half before a charge is necessary.

Loving the Beaver!
Jason, Sherri, Christian, & Wheeler (Golden Retriever)
2008 Beaver Contessa Huntington CAT C9 400hp FMCA F25478 S4
FunGus is offline   Reply With Quote
Old 08-31-2015, 08:38 PM   #3
Senior Member
Join Date: Jul 2014
Posts: 11,732
If you treat it like you do, it will give you the same service.

Considering the abuse, they served you well.

A Trojan 8 D is 230 Ah. The same as 2, 6 volt GC2s. Very heavy!

You loose half of your capacity unless you get 2.

Your lack of maintenance makes you a candidate for AGM.

No water to check or add, no fuzzy terminals, but 3 times the price.

If you don't keep AGMs charged to 100% while stored, they will only last as long as wet cell batteries.

Good luck
twinboat is online now   Reply With Quote
Old 08-31-2015, 08:39 PM   #4
Senior Member
Mr_D's Avatar
Winnebago Owners Club
Solo Rvers Club
iRV2 No Limits Club
Join Date: May 2011
Location: Vancouver, WA
Posts: 31,225
In our '02 DSDP the Interstate U-2200's went 10 years and were still good enough to last overnight with the normal use of lights and TV. In 2004 I put 4 oz of mineral oil in each cell so that cut way down on the water usage and corrosion. In fact the tray and holddowns looked almost brand new.

Our present rig had 4 8D AGM's and 4 925 CCA sealed starting batteries. The specs said it should have had 2 8D AGMS for the starting batteries but for some reason it didn't.

Anyway, about two months ago I replaced the starting batteries with 4 925 sealed batteries. Yesterday I replaced the 4 8D AGM's with 4 8D wet cells. Got the new 8D's from Interstate for $190 each which was $60 less than list. For our use I just couldn't see paying between $500 and $700 per battery!

This gives us 3700 CCA and 1180 amp hours at 20 amp rating. I have room for 2 more 8D's if I need it.
2009 45' Magna 630 w/Cummins ISX 650 HP/1950 Lbs Ft
Charter Good Sam Lifetime Member, FMCA, SKP
RV'ing since 1957, NRA Benefactor Life, towing '14 CR-V
Mr_D is offline   Reply With Quote
Old 08-31-2015, 08:53 PM   #5
Senior Member
Smitty77's Avatar
Join Date: Aug 2010
Location: Over the next hill, around the next curve...
Posts: 3,498
Scott - Off of memory here, so may not be accurate!

Usually X's 4 6V GC batterie will have the same foot print (or close enough with a man of your fabrication skills) as X's 2 8D's.

And, if your battery bay has enough headroom towards the top, you can also usually finesse X's 4 6V L16's.

With 40% boon docking, the extra Amp Hours means less need to run the generator, and at the same times provides a good margin of extra 'safety capacity' - for just in case.

And yeah, two 8D's or four L16's are more expensive then four golf cart 6V's!

You also mentioned an occasional need to for 'catch up maintenance' on your battery compartment. Again, in an effort to help you spend $$, you have just made the best argument for AGM's! (And a second good argument, at 40% boon docking, is the much faster recharge times of AGM's over wet cells. (With a charger that can properly support AGM's, suspect your coach has this optional setting available(?).)

We replaced our two house 8D's AGM Deka's (Just about toasted when we bought the rig.), with four Lifeline L16's for 800AH. Other then blowing out dust from the battery compartment, I have not had to maintenance the cables for going on three years now. We have lots of toys (Got tubes? For my HiFi), residential fridge, etc., etc. - and I honestly do not try to conserve power overnight. With a start of 100% SOC at night time, some music, microwave, convection of up to 20 mins (If running more then 20 mins, I have my wife fire up the generator. DirectTV, TV, etc.. I usually wake up and fire up the electric coffee pot, wait about 20 mins, then check SOC. Usually in the 75-80% range. (If we tried to conserve more, I'm sure we could have 80% + SOC on those readings in the AM.)

Who cares about SOC? Well batteries have "X" amount of charge/discharge cycles available to them. So, my thinking is that a battery bank that is more robust, and does not discharge to a lower percentage SOC, has a longer life. And, I very seldom am not back to a full 100% SOC by early afternoon, with only the Solar Panels charging the Lifelines. When I'm in the shade too much, or heavy clouds, I'll never let the bank go for more then two days, without running the generator if needed to bring them back up to a full 100%. (Probably needed to do this less then 12 times since I installed the battery bank and solar panels.).

So, I'm hopeful buy less discharge, and keeping the battery properly topped off on a regular basis, that I will get between 8-10 years of good performance out of the Lifelines. (Expect this to be the same for any AGM, or wet cell for that matter.)

So recap:
-More money upfront to buy AGM's
-Easier care over hopefully 8-10 years
-Higher reserve capacity for emergencies
-Hopefully longer life, will recoup some of the costs
-But, nothing is as inexpensive as a wet cell. Even if replacing more often due to 'Oh yeah, I really should check the water in those batteries!'

No wrong or right on this one, just choices on pay me now, pay me later, maintenance me over my lifetime, or install me and forget me over my lifetime!


Good luck on our research, and you will posts form the both camps. The wet cell is the only way to go group, and you're just tossing our money away with AGM's camp. And then the you get what you pay for and ease of maintenance and faster recharge times and possibly longer life out of the AGM's camp... And you know, as in all sides, many times it just comes down to what you want to do!

Best to you,
Roo II is our 04 Country Coach Allure 40'
OnDRoad for The JRNY! Enjoy life...
Smitty77 is offline   Reply With Quote
Old 08-31-2015, 10:56 PM   #6
Senior Member
FIRE UP's Avatar

Join Date: Dec 2009
Location: Out there, somewhere
Posts: 5,942
Well Men,
I surely do thank you all for contributing to my inquiry. I was not aware that 8D batteries had been used for house batteries. When I first entered the FD in '80, we had 8Ds for our fire trucks. But, as time went on, we migrated to Optimas for way less maintenance. So, I've had no contact with 8Ds for a long, long time. Well, in checking around for potential replacements for our Costco units, I thought of the 8D.

Without a doubt, your advice here is totally outstanding. I have considered the AGMs and, all the benefits of them. But, I'd have to sell the dog, the wife, my first born who's 32 and lives in another state, to get those AGMs. I surely would like "top of the line" batteries, no doubt about that. And, you know me, I'm not in a habit of "poor maintenance". It's just one of those things that I need a kick in the pitutie once in a while.

Now, one thing here. With my old Dimensions Inverter/Charger, it would automatically do an "Equalizing" charge/cleansing every 5th cycle of being plugged in. But, with this new, Magnum ME2012 MSW Inverter/Charger, that I've had in there now for, oh, about a couple of years, the only way it equalizes is, If I do it manually.

Just for possibility of extending the life, I maybe should do an equalization run on them. But, since this has to be done manually, I have no idea what I would be doing. I was cruising around on Magnums site last night and found the owners manual for my Inverter/charger but, it says nothing about equalizing. I'll have to dig further.

Anyway, AGMs might not be out of the running. I'll take a look at all options.

And Smitty, when I spoke with the Interstate rep this afternoon, he gave me the dimensions of the 8D. Basically, a single one, will fit in my house battery tray with about an inch to spare, all the way around. And, that battery is 160 lbs. So, in all reality, there' no way on this planet, or, our motor home, that TWO 8Ds will fit.

The coach came from the factory with (3) group 27 12V Interstate so-called Deep Cycle/Marine batteries for house batteries. Well, they were replaced by three more of the same, about 8 months before we purchased the coach. We really didn't get a chance to camp in it before one of them developed a bad cell. I exchanged it with a semi-warranty new one. I say semi 'cause it still ran me about $67.00 to replace it.

Well, guess what, about a month after that replacement, another one developed a bad cell. So, all of the were shi...canned in exchange for (4) 6V Costco ones. I rewired the system to accept all the new 6V units. For the most part, they've served us well.

There is a very slight amount of bulging in a couple of them, not bad, just barely there. I'm thinking I'm at a cross roads here. They're four years old, (many report double that out of theirs) and, I'm not sure they're up to the chore of keeping going in even the limited amount of dry camping we do.

Again, I'm really appreciative of all the help here. I'll keep considering all avenues.
2004 ITASCA HORIZON 36GD, 2011 GMC Sierra 1500 4x4 Toad '08 GL 1800 Gold Wing
Retired-29.5 yrs, SDFD, Ham - KI6OND
Me, Karla and the Sophie character, (mini Schnauzer)
FIRE UP is offline   Reply With Quote
Old 09-01-2015, 05:38 AM   #7
Senior Member
mgscott4's Avatar
Workhorse Chassis Owner
Join Date: May 2009
Location: Kansas City, MO./Pollock, LA.
Posts: 1,550
4 -- 6 volt batteries worked for you for 4 years.

Shop around, you can find 6 volt batteries for under $100 each (Sam's Club). Then buy your own turkey baster, and remove 4 oz of acid from each cell and replace it with "mineral oil" available at Walmart in the pharmacy section. The mineral oil will help breakup the gassing and corrosion will be a thing of the past. Purchase this water filler and once every other month, (set your calendar on your smartphone) fill your batteries.


This is your least expensive option, AGM batteries will cost a good deal more.
06 Hurricane 34FT WH W20 Chassis 8.1L 132K, Steersafe, Koni Shocks, DIY Trac Bar, Tri-Metric 2025RV Battery Monitor, 4-6V Batteries, Scan Gauge 2, Crossfires, 735W Solar Morningstar MPPT-60, WG T4 In-Motion Sat, XM Radio, 07 Chevy Malibu Maxx Toad, Falcon 2, Brake Buddy, Escapee
mgscott4 is offline   Reply With Quote
Old 09-01-2015, 08:17 AM   #8
Senior Member
Winnebago Owners Club
Join Date: Feb 2008
Posts: 728
Fire Up

The fact that the 8D is 160 lbs would stop me from purchasing. After altering my slide out tray I went with 4 Costco golf cart batteries. I to also added mineral oil and have not had any corrosion or "things growing" on my terminals or tray. I've had them for 2 plus years with no problems. I believe they are the most cost effective choice and bang for the buck.

Good luck with your decision.
charles tuit is offline   Reply With Quote
Old 09-01-2015, 10:45 AM   #9
Senior Member
wa8yxm's Avatar
Damon Owners Club
Workhorse Chassis Owner
Join Date: Mar 2009
Posts: 23,869
Found what I was looking for... U.S. Battery | Leader in Deep Cycle Batteries | Battery Specifications | U.S. Battery

If you scroll to about the bottom of the page you will find the 8D listed, 240 amp hours.

Their US-2200 which is a GC-2 size is either 216 or 232 amp hours both at the 20 hour rate

S0.. that is close enough (less than 10 % difference) to say "no practical difference)

The differences are: 8D is a single battery that replaces 2 GC-2's
8D is twice as heavy \
8D is thus 4 times harder to install
8D usually costs more.

Your choice. (With six volt batteries when you pair them in series you add the VOLTAGE.... Amp Hours do not change)
Home is where I park it!
wa8yxm is offline   Reply With Quote
Old 09-06-2015, 10:28 AM   #10
Senior Member
Join Date: Jun 2007
Posts: 138
Originally Posted by charles tuit View Post
Fire Up

The fact that the 8D is 160 lbs would stop me from purchasing.

I have 4 Lifeline AGMs. They are 9 years old. Never a bit of trouble. Will replace next year, just because of age. I would never have anything else. 440 total amp hour capacity. I have not researched the 8D, but the weight and the 'all eggs in one basket' concept troubles me.

2006 Itasca Horizon 40KD, 2004 Honda CR-V
NoMoreAZ is offline   Reply With Quote
Old 09-06-2015, 11:04 AM   #11
Senior Member
1ciderdog's Avatar

Join Date: Jun 2010
Posts: 4,366
I had 8-D's in a boat and they were good except (as mentioned above) the weight. At my current age I wouldn't/couldn't deal with the weight of those batteries. Regular golf car batteries now seem to be very heavy but I can still handle them so if it were me I'd go to Costco and get the 6 volt batteries they sell.
Bob, Sandi & Marmaduke the Big Pug
SW OREGON 2004 Journey 39K, 330 Cat
If towing: a 2006 Mini Cooper or 2015 RAM Limited 4X4
1ciderdog is offline   Reply With Quote
Old 09-06-2015, 02:40 PM   #12
Senior Member
Join Date: Nov 2012
Location: bis. nd
Posts: 729
I have over the years bought many of the reconditioned or returned batteries at less than half cost of new..and when I do buy them I have a load test on each to make sure they pass...when my alternator diodes went out a few yrs a go I needed two starting batteries..i bought the two for 95 bucks with tax at interstate. and there still like new..heck I can replace em twice if had problems...jeff
2007 Alfa Gold!! model 1008. 400hp Freightliner, IFS!!
beenthere is offline   Reply With Quote
Old 09-06-2015, 04:22 PM   #13
Senior Member
rgvtexan's Avatar
Winnebago Owners Club
Freightliner Owners Club
Join Date: Oct 2009
Location: NE WA or S TX
Posts: 2,479
In my 04 Horizon QD I have 4 Costo batteries (July 2010). The Profill system fits and works very well.
It's been awhile but I seem to remember it was a little tricky to install with the low clearance. I installed the plugs into the batteries, put in tray and then snapped the manifolds on. It's close, but slides in/out with no problem. In Costco last week batteries were ~$83 each in Spokane. ymmv

04 Horizon QD, 12 Ford Flex, Excalibar, Brakemaster, Winter Texan, RVin! since 1974
Norm, Donna & Tinker Kat 74 MGB-GT, 75 MGB, 01 Z3
Life is a Timed Event, you only get One Go Around!
rgvtexan is offline   Reply With Quote


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
House battery draining REBSIDDALL Class A Motorhome Discussions 2 07-12-2015 10:33 AM
Battery tray too small or new house batteries to large RockyMtnRide Monaco Owner's Forum 11 06-06-2015 06:58 AM
House Batt Chassis Batt Charging Jamie65 Tiffin Motorhomes Owners Forum 5 02-06-2015 06:48 PM
House Battery drain Rburian Monaco Owner's Forum 14 05-29-2014 06:01 AM

» Featured Campgrounds

Reviews provided by

Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 03:29 AM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, vBulletin Solutions, Inc.