Battery sizes ... I just don't understand.

[rcebowl]

Hi Guys I'm hoping someone can explain something to me.

I'm looking to replace my battery (OE 27) and I see that people are upgrading to 35 or 34 and even 31s.

But what i don't get is outside of a 31 (which is a good size bigger) the 34 and 35 actually are physically smaller as well as lower CCA and AMP hour than a 27. So why are 34 and/or 35 considered an upgrade to the 27? they are similar weights as well.

Picture for comp but similar results with other brands too

 

[Bumbo]

I went with a 24F as a OE replacement... seems ideal to me from a size standpoint.

I think its worth mentioning that not all batteries are created equal... you might be seeing some spec variations based on internal construction and design.

Generally speaking... higher the CCA value is, the worse it is in deep cycle duty, the the opposite is true for a deep cycle.

Both can start the truck, but each will excel in different areas.

The physically larger cell just gives you a little extra reserve, even if it can't deliver more CCA which is really the core focus of a starter battery, its ability to deliver large amounts of amps in a short duration.

Really, if it fits in the tray and starts the car, its about all that really matters unless you have some other special application you need it to work with. I can spend hours reading about this stuff, but it's not something that actually requires any over-thinking.

 

[riceandpho]

if you have alot of accessories, i go the biggest, northstar group 31m or standard will require a mod to the negative post, it will hit the hood. i took that out and did bolt with a lock washer.

group 27f will fit like stock. group 24f will fit, just smaller.
34r will need a spacer on the bottom since it will sit lower.

since you will have the battery out, do a big 3 upgrade, good thing to beef up the charging system. 4 gauge is a nice upgrade, but if you want to be future prof go ahead and do 1 gauge wires. use OFC, do not use CCA, you will see a big difference in price.

 

[akcc]

You can always go for group 49 battery, it fits in the 4runner without any mods. Only thing it is a bit wider than stock and will sit off the rim/lip of the battery tray but.. you get 850-950cca and around 900-1050amps with usually 150-200mins reserve run time.

 

[kingofthehill]

From what I was reading the 24 and 27 are the stock group size for the Toyotas. The 27 is recommended for colder climates due to its larger capacity. The 27 batteries are also less common so finding these batteries in a specific brand can be hard and sometimes require special order. I went with an X2Power 24F battery when I bought my last battery due to the 27 version being a special order at my local Batteries plus. I figured that I don't have any need for the larger size and that the 24f outperformed most other 27 series batteries from other manufactures. It is also a plus that if I need a warranty replacement I wont have to wait for a special order to arrive.

 

[Ralph Blake]

I have tried many batteries over the past 50+ years, and i have found that going to Walmart and getting their Ever Start Maxx 24F is right for both my two Autos my V-6 4runner and my V-6 Nissan Maxima.

And so far it's been a really good choice, if i have a problem there are many Walmarts around.