Forum Discussion

smlranger's avatar
smlranger
Explorer
Oct 07, 2013

Deep cycle battery choices

My coach has 2 8D Deka AGM house batteries. They were installed by the previous owner in 2011 but I think they were neglected/depleted while the coach sat on the dealer's lot. They charge up but don't seem to have much staying power.

I am considering replacing with Duracell AGM's GC2 6 volts from Sam's. I understand they are actually made by Deka and Sam's offers an 18 month full replacement warranty. I will likely go with four or maybe even 6 of them since I have the space (the battery bay was designed for four 8D batteries which are pretty big).

I am curious if anyone has any experience with these particular batteries.

10 Replies

  • Thanks for the suggestions.

    I do have one of the 'hot wire' automotive load testers. When I first got the coach, the Cummins Coach Care shop doing some chassis service/checking told me one of the two 8D's tested weak. When I got the coach home, I used my load tester (disconnected both batteries and let them sit before testing) and both of them tested fine.

    Recently I had the coach in the shop for 11 days while having a defective inverter replaced. Unfortunately, the house 12V power was left on for the entire time and when I got the coach, the house power was at 9.6 V. After charging the batteries to float charge level, I load tested them again and they both tested strong.

    However, if I disconnect shore power and let the inverter run, voltage drops pretty quickly (I have large Amana residential fridge)....drops from 12.6 to 12.2 in less than 2 hours. The two batteries are 490 amp hours.

    I also note that whenever I start the genset without the coach engine running, it seems to crank very slowly...struggles to start. Since the house batteries crank the genny (10KW), I am wondering if they just are not up to the task. I have AGS but wonder if the batteries will start the genset if I let them fall to the 'start level' I have set which is 12V.

    I know the coach came from the CC factory with four 8D's but if I have to replace batteries, I wanted to switch to batteries I can physcially handle. We do not boondock other than an occasional night in a Walmart lot.
  • Disconnect each battery and have them checked individually. A set of batteries tends to discharge to the point of the lowest battery. If you have one battery that is bad, it will drag all of the others down to it's level. Rather than spring for all new batteries, you need to find out if replacing one is all that you need and this can only be done by disconnecting the batteries and checking them one at a time.
  • I've bought Interstate, Deka (name brand) and now have the Sams' Club version of Deka.
    Seems not matter what "premium name brand" or "off brand"...like Sams' Club, I get 3-4 years out of my 12V and 2- 6V batteries.

    No now, with that in mind, I go for the price. Not the name.
  • Hi,

    It is a gentle equalization charge. Are the batteries wired in a balanced manner?

    smlranger wrote:
    When you refer to 'conditioning' charge, is that the same as an 'equalizing' charge?
  • My experience with AGM batteries is that if you run them down t zero a few times it will damage them. The place where I used to store my coach was maned by the three Stooges and they killed new 8D AGM's in less than two years.

    I would suggest sticking with what the factory put it originally. 4 8D AGM batteries. My batteries came with a 5 year warranty. When the Stooges killed them most of the replacement cost was no charge. Not all but most.
  • When you refer to 'conditioning' charge, is that the same as an 'equalizing' charge?
  • dons2346 wrote:
    pianotuna wrote:
    Hi,

    I'd try a conditioning charge on the 8d's first. There is nothing to loose by doing so.


    Same here

    X3

    Besides, the Duracell AGM is made by Deka (actually East Penn Batteries).
  • pianotuna wrote:
    Hi,

    I'd try a conditioning charge on the 8d's first. There is nothing to loose by doing so.


    Same here
  • smlranger wrote:
    My coach has 2 8D Deka AGM house batteries. They were installed by the previous owner in 2011 but I think they were neglected/depleted while the coach sat on the dealer's lot. They charge up but don't seem to have much staying power.

    I am considering replacing with Duracell AGM's GC2 6 volts from Sam's. I understand they are actually made by Deka and Sam's offers an 18 month full replacement warranty. I will likely go with four or maybe even 6 of them since I have the space (the battery bay was designed for four 8D batteries which are pretty big).

    I am curious if anyone has any experience with these particular batteries.


    Bought 4 in March from Sam's. Have done 2 dry camping music festivals with a house full of folks since installation (5 adults for 4 days, 3 adults for 5 days).

    Ran the generator very little at both festivals (only when we needed A/C) and the Duracell's were robust for both events.

    We did not run the inverter as we cooked on the propane stove, or grilled outside, fridge on propane and we don't watch TV or movies when we are at the festival(s).

    The Duracell's quickly came back to fully charged after both events.

    A big thumbs up from me and the price was fantastic.
  • Hi,

    I'd try a conditioning charge on the 8d's first. There is nothing to loose by doing so.