Start Battery Questions!

Topic: Start Battery Questions! (Read 921 times) previous topic - next topic

Start Battery Questions!

December 12, 2021, 12:18:39 pm

Getting ready to upgrade our start batteries in our coach. 450 M11 engine! Can someone please explain the difference between Group 31, 34 and what ever other group that is out there? Also, have heard that Optima's are a no go now, so what do you all recommend? Thinking on 850 CCA for AGM start batteries as well. Will be upgrading the positive/negative posts on engine and whatever else we need to do. Have learned much from Rogers upgrade! Many thanks to all who have paved the way before me!
So, what say you pros out there?

Thanks in advance!

Re: Start Battery Questions!

Reply #1 – December 12, 2021, 12:44:30 pm

Group 31 have more CCA but are longer, possibly requiring a modification to the battery rack. $300 for all three with quantity discount in 2019. See my old post. We now have 2850 CCA but 3000 is possible with other brands. They should weigh 60 lbs each or more. Lots of sources, just do a Google search and compare. Impossible to have too many CCAs.

Pierce

Re: Start Battery Questions!

Reply #2 – December 12, 2021, 12:50:18 pm

Quote from: Pierce & Gaylie Stewart – December 12, 2021, 12:44:30 pm

Group 31 have more CCA but are longer, possibly requiring a modification to the battery rack. $300 for all three with quantity discount in 2019. See my old post. We now have 2850 CCA but 3000 is possible with other brands. They should weigh 60 lbs each or more. Lots of sources, just do a Google search and compare. Impossible to have too many CCAs.

Pierce

Thanks Pierce, now I see what the difference is. Really don't want to rebuild the battery rack if possible.

Re: Start Battery Questions!

Reply #3 – December 12, 2021, 01:05:52 pm

Your coach probably came with three 24 series. Plenty normally. We camp a lot at 8000 feet or more so better in high cold weather with 31s.

Pierce

Re: Start Battery Questions!

Reply #4 – December 12, 2021, 01:48:10 pm

Quote from: juicesqueezer – December 12, 2021, 12:18:39 pm

Getting ready to upgrade our start batteries in our coach. 450 M11 engine! Can someone please explain the difference between Group 31, 34 and what ever other group that is out there?
So, what say you pros out there?
Thanks in advance!

Group 31, 34 and what ever other group that is out there in commercially manufactured batteries refer to a size standard called the BCI Group Number set forth by the Battery Council International. The BCI number refers to the physical dimensions of the battery and not the Amp Hours (AH) capacity. And have no rhyme 'nor reason.

Bigger is better. Heavier is better. Lead-acid battery sales literature is slipperier than a snake. Try to reduce your comparisons to amp hour capacity at a specified discharge rate. Written as 250 A/H @ 20A.

FWIW I have a BCI Group 24 Interstate AGM powering the starter in my 903cc Siata.

Re: Start Battery Questions!

Reply #5 – December 12, 2021, 01:51:37 pm

Only comment is that for starting batteries, pay more attention to CCA (Cold Cranking Amps) than amp hour capacity.

Amp hour capacity IS the number to consider for house/deep cycle use.

And several times a year, many Freightliner truck dealers put their truck starting batteries on sale. They are good batteries.

Re: Start Battery Questions!

Reply #6 – December 12, 2021, 01:53:07 pm

Why are Optima batteries a "no go" now?

Re: Start Battery Questions!

Reply #7 – December 12, 2021, 02:52:50 pm

Physical dimensions of BCI Group 31 batteries are approximately 13 x 6 13/16 x 9 7/16 inches (~13 x 6.8 x 9.44 inches, 330 x 173 x 240 mm), and they weigh anywhere from just under 30 pounds (lithium batteries) to almost 80 pounds (lead-acid batteries).

10.25 x 6.8125 x 7.875 inches
BCI group 34 batteries physical dimensions are (L x W x H) 10.25 x 6.8125 x 7.875 inches (26 x 17.3 x 20 cm), with the weight varying between 37 and 51 pounds. BCI group 34 batteries are very similar in size to BCI group 24 batteries (10.25 x 6.8125 x 8.875) - group 24 batteries are 1 inch taller.

Re: Start Battery Questions!

Reply #8 – December 12, 2021, 02:58:50 pm

Quote from: D.J. Osborn – December 12, 2021, 01:53:07 pm

Why are Optima batteries a "no go" now?

So I used to be the Optima poster child. I had nothing but good things to say about them. They were the best. Then they sold and like many items were no longer manufactured locally. The new owners located to south of our border and reduced costs in manufacturing. They also lost 20lbs of weight. Warrantee reduced to three years like Walmart. 38 months later you were replacing them. Other than no leakage there was no reason to pay premium prices for a average battery. Off my approved to purchase list.
Scott

Re: Start Battery Questions!

Reply #9 – December 12, 2021, 03:24:49 pm

Quote from: dsd – December 12, 2021, 02:58:50 pm

So I used to be the Optima poster child. I had nothing but good things to say about them. They were the best. Then they sold and like many items were no longer manufactured locally. The new owners located to south of our border and reduced costs in manufacturing. They also lost 20lbs of weight. Warrantee reduced to three years like Walmart. 38 months later you were replacing them. Other than no leakage there was no reason to pay premium prices for a average battery. Off my approved to purchase list.
Scott

If I want to replace my current starting batteries with Group 34 batteries with at least 800 CCA then what should I use?

Re: Start Battery Questions!

Reply #10 – December 12, 2021, 03:41:01 pm

Joe, Group 31 batteries fit in my 2001 U320. Check you rack dimensions.

I replaced my very worn Optimas after about 6 years, they were toast. I used these. https://www.oreillyauto.com/search?q=Oreilly+super+start+AGM31T

I didn't want to have wet battery maintenance added to my list of chores.

$205 each out the door.

It is not generally recommended to use Lithium batteries as start batteries.

Re: Start Battery Questions!

Reply #11 – December 12, 2021, 03:41:33 pm

Joe, I'm about done with my mailbox so if you want co come on over I should have enough left over material to build you a battery box-- plus it will be stainless steel lol!
Chris

Re: Start Battery Questions!

Reply #12 – December 12, 2021, 05:12:20 pm

I have group 34's. All this information helps! Chris, if you weren't so far......
Appreciate the jester!

Re: Start Battery Questions!

Reply #13 – December 12, 2021, 05:24:05 pm

Quote from: juicesqueezer – December 12, 2021, 05:12:20 pm

I have group 34's. All this information helps! Chris, if you weren't so far......
Appreciate the jester!

My Optima Red Top batteries (Group 34) are 9 years old and still appear to be okay. When I need to replace them I will likely go with O'Reilly SuperStart AGM Group 34 (unless someone has recommended a better replacement).

Re: Start Battery Questions!

Reply #14 – December 12, 2021, 05:24:30 pm

HATE BATTERIES really wish I could recommend. I purchased NAPA group 31 3/8 stud top and during purchase Napa salesman said they were junk. Worked for last year and a half. I never use boost during start and they do fine.
Scott

Re: Start Battery Questions!

Reply #15 – December 12, 2021, 05:24:51 pm

We just use maintenance free conventional batteries. They never lose any electrolyte/water. The batteries we purchased in 2008 lasted until 2019. If you keep about 13.2 to .5 volts on them all the time without fail, they should last ten years. They are Autozone but others are also good. 31 series are considered commercial batteries and have shorter warranty.

Pierce

Re: Start Battery Questions!

Reply #16 – December 12, 2021, 05:30:40 pm

Our Opti Red Tops are 11 years old....recently noticed our charger led indicator was getting lower and lower after a week it was down to 12.2V (coach in barn). Decided to pull Opti's, charged and load tested each...showed great voltage under load and held after the test. Discovered my external charges was "kapput" got a new battery tender and everyone is happy. Hope I didn't jinks my red heads

Re: Start Battery Questions!

Reply #17 – December 12, 2021, 05:43:08 pm

Quote

If I want to replace my current starting batteries with Group 34 batteries with at least 800 CCA then what should I use?

I got mine (only 2 for the 8.3 in the 270) at O'Reilly's. 800 CCA.

I'm with Scott on Optimas. I used them in other rigs and they performed fine. However, the set that was in this rig when I got it six years ago failed early. I replaced them with Optimas and they too failed early.

Here's the O'Reilly battery that I bought.
jor

Re: Start Battery Questions!

Reply #18 – December 12, 2021, 06:24:04 pm

Quote from: jor – December 12, 2021, 05:43:08 pm

Here's the O'Reilly battery that I bought.

I would prefer group 31's as they're pretty common around trucking, cheaper, heavier, and have about 1000 CCA each, but they won't fit my battery rack as-is (too long and too wide). A replacement battery rack is on my list of things to do.

Today, I have to have group 34's. My starter requires 2400 CCA on the M11, so I need 3x 800 CCA group 34's.

I would choose the O'Reilly's over Walmart, but the O'Reilly's are frequently unavailable here and I need three when I need them. Walmart consistently seems to have ten or so in stock for much less money -- but they have vents, so presumably would need to be topped off from time to time.

If I bought batteries at home, I'd probably see what O'Reilly could get me that were 800 CCA or over. If I was on the road, I'd probably head to Walmart for three of theirs. Finding 800 CCA group 34's in a pinch is challenging. It's nice to have options.

Really annoying: "What year, make, and model are you getting batteries for?"

Re: Start Battery Questions!

Reply #19 – December 12, 2021, 06:48:50 pm

So in thinking of the "Hate batteries comment I made earlier I must disclose I live in the worst place in the world for batteries (desert) and I own and maintain 25 batteries in all. Cars, boats, MH, trucks, forklift, backhoe, motorcycles, and toys. Only thing worse than batteries is tires. Need to thin the herd!

Re: Start Battery Questions!

Reply #20 – December 12, 2021, 07:38:22 pm

Quote from: dsd – December 12, 2021, 06:48:50 pm

Cars, boats, MH, trucks, forklift, backhoe, motorcycles, and toys... Need to thin the herd!

I'm interested in at least half of those when you do

Re: Start Battery Questions!

Reply #21 – December 12, 2021, 08:46:22 pm

We have had 3 Optima batteries for engine in used for over 3 years that work great. I would recommend red-top Optima.

Here is our purchase note:

Optima Red-34/78-980 (aka 8004-003, 9004-003, 27990, N9934/78RED) From NAPA, $185 each

Re: Start Battery Questions!

Reply #22 – December 13, 2021, 09:08:57 am

Quote from: trailertrashrick – December 12, 2021, 06:24:04 pm

Really annoying: "What year, make, and model are you getting batteries for?"

Rick, this is for my 2000 U320 M11 cummins! I measured the rack and batteries again and it looks like I can only use batteries that are just a little over 10 inches long, which puts me in the group 24 range. May have to pull the rack and have it enlarged to find the heavier batteries that I would like to have for the engine!
Many thanks to all who responded and I have gained some knowledge on batteries and what to look for in my purchase. We will be here awhile in TN, so will take the time to do some more research!

Re: Start Battery Questions!

Reply #23 – December 13, 2021, 09:39:47 am

Quote from: trailertrashrick – December 12, 2021, 06:24:04 pm

Really annoying: "What year, make, and model are you getting batteries for?"

Quote from: juicesqueezer – December 13, 2021, 09:08:57 am

Rick, this is for my 2000 U320 M11 cummins!

I think TTRick was making a humorous reference to auto parts counter automatons who always ask you what model car the requested part is for. They apparently can only conceive of buying a part (battery, etc) for one specific application, and have only one way of identifying a part in their inventory. I also have been asked this question too many times to count...and feel the same frustration.

Re: Start Battery Questions!

Reply #24 – December 13, 2021, 10:01:34 am

Quote from: juicesqueezer – December 13, 2021, 09:08:57 am

Rick, this is for my 2000 U320 M11 Cummins!

Joe, when Rick wrote "Really annoying: "What year, make, and model are you getting batteries for?" it was meant as a rhetorical comment possibly with a tinge of irony. Why? Some of us are tired of walking into the parts store and asking for, in this case, "I'd like three Group 31 batteries please" and have the return from the clerk "What year, make, and model are you getting batteries for?" knowing full well that "1997 U320 4000 WTBI Build 5152 "Molesley" will not be in the parts house' computer system.

Good for you for going with what I like to term "enough" battery. Nothing succeeds like excess! Oscar Wilde.

Affiliate Notice