Group 31 vs. group 34

[TexasLefty]

I have seen where several people do this conversion and my question is why? I understand a few more cranking amps and I understand that getting the batteries out of the engine compartment and getting away from lead acid are a good idea, but why the group 31?

I have searched for a thread on this topic and was unsuccesful. I am really only interested in how and why this is necessary in the IDI's?

Thanks in advance for looking or responding.

 

[icanfixall]

Its not really necessary but its a nice upgrade to the starting system. The 31 battery is what the big rigs use and it has the lug top posts. Its a much betting idea than the usual lead clamp on posts. Much easier to keep clean too. Better cranking power too. Its also a cheaper battery and you get much more for what you pay compared to the 34 battery. A diesl makes lots more natural vibration than any car or gas engine does. A car battery never stands a chance in a high compression diesel. The vibration ruins them in short order. Kinda a little known fact too. Plenty of members have converted to the lug top 32 but some modification needs to be done. The battery tray needs to be cut so the battery fits down in it. The cables needs to have the ends changed too. When all is said and done the 31 upgrade is much easier toconect or unconnect.

 

[redmondjp]

Well-stated above. The heavy-duty Group 31 batteries have additional design features inside which make the batteries more resistant to shock and vibration (which can cause open connections and/or shorted-out plates internally) that they can encounter on a commercial truck. You will pay more for a heavy-duty version which I would recommend. Expect to pay $100 or more for one.

Plus, Group 31s are made in high volumes, so are easy to obtain everywhere. I'm going to switch my truck over to a Group 31 battery later this year (has a tired 10-year-old Optima in it now).

 

[TexasLefty]

I plan to move the Batteries to the frame under the cab, if that changes anything.

If I understand correctly you are saying a group 31 lead acid is more reliable than a group 34 AGM?

 

[ocnorb]

I plan to move the Batteries to the frame under the cab, if that changes anything.

If I understand correctly you are saying a group 31 lead acid is more reliable than a group 34 AGM?

More weight in Lead= more reliability, strength. Plus, like the guys above state - they are used in every big truck on the road so getting replacements is easy.

You want the baddest- watch this: http://www.youtube.com/watch?v=E7bOF94Iq70

 

[purg113]

how about getting some pics of the diffrent battries so some of us that have no idea what we are trying to look for

 

[ocnorb]

how about getting some pics of the diffrent battries so some of us that have no idea what we are trying to look for

You must be registered for see images attach

 

[TexasLefty]

That was impressive! It looked like a group 34 and it also appeared to be AGM.

Just googled it and it is about $220 and its AGM. The Deka is only $20 more and has a better warranty.

 

[ocnorb]

That was impressive! It looked like a group 34 and it also appeared to be AGM.

Just googled it and it is about $220 and its AGM. The Deka is only $20 more and has a better warranty.

The Sears Platinum is a rebadged Odyssey battery.

 

[TexasLefty]

The Sears Platinum is a rebadged Odyssey battery.

Wow!! If thats true thats cheap!!

 

[franklin2]

I have seen where several people do this conversion and my question is why? I understand a few more cranking amps and I understand that getting the batteries out of the engine compartment and getting away from lead acid are a good idea, but why the group 31?

I have searched for a thread on this topic and was unsuccesful. I am really only interested in how and why this is necessary in the IDI's?

Thanks in advance for looking or responding.

You are thinking correctly. Unless you have some special circumstances your truck runs under, the heavier duty battery is not necessary. I guess it's one of those "I am cool because I am running big rig batteries" deals. If your engine/glowplugs/starting system are in good shape, you really need only one regular battery to get it started in warmer temps. I have done it temporarily as have many others on here in a pinch. What does that tell you?

 

[Exekiel69]

I have group 31 batteries on My trucks, are they necessary? maybe not, but why do we put turbos on this engines anyways... we can pull the same load just fine.

I've seen My self (as I'm sure many others have) in a situation where I need to start My truck and I have air in the lines, or the temp outside is very low and I was glad I have larger batteries instead of regular ones.

When I do mine I usually pull the battery tray and all the brackets and make new brackets to lower them about 2", by doing this I'm sure it will not touch the underside of the hood.

 

[jwalterus]

I have 31s in my truck..... and every other vehicle I have (including the wife's V-6 astro), simply because I believe in 1000CCA living in ND (and I can get AC Delco ones for $115 each with a 72 month full replacement)

 

[gonecrazyi]

I've used interstate and Autozone batteries and they didn't crank anywhere near as fast as my g31s. I also found a set with normal style posts so I didn't have to change my terminals. With a standard starter I can start my truck in 15-20 seconds when no Glowplugs after a week of sitting.

 

[93cc7.3]

I have 31's frame mounted infront of the rear tires and I love them made a world of diffrence