Are AGM Batteries an improvement over typical lead acid battery?

[CrRusty]

It seems like the availability and costs of AGM batteries have come along way in the last few years. I have an AGM (walmart)battery in my 2003 TDI Jetta for almost 9 years now, its still going strong.

Did a search in Bay and Vanagon land but did not turn up much info. I think the AGM are still not yet popular.

So Im thinking of replacing the starting battery in my Bay window with an AGM battery. The baywindow buses are unique since the aircooled engine (2ltr) creates a lot of heat compared to watercoolers, especially when turned off on the summer, and the battery is sitting above the muffler. Will the extra heat be enough to damage the AGM battery any differently than that of a flooded lead acid battery? We also have small output alternators.

Currently can get a 4 year free replacement AGM battery at Popboys for $147.
Appears to be a no brainer, but maybe others have some insight to share?

[aeromech]

Here's mine. It's been working great

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[WhirledTraveller]

AGM's are just plain better than regular flooded batteries for starting use. No acid spill, more starting current, less self discharge. If you don't store them discharged they last a long time.
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1977 Westy, Automatic. Big Valve heads, CS Cam.

[Clatter]

I quit using AGM and went back to regular lead acid types.

Two reasons:

1. OG USA Optimas are overseas now and do not last long at all.

2. AGM doesn't like to sit; unless you trickle charge them they lose charge.
And then never fully recover..


Post your -recent- experience,
And it will be different than it was a few years ago..

So many things like this in the hobby now;
You would think at least batteries would be exempt FFS!
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Bus Motor Build

What’s That Noise?!?

[a-marshal]

[WhirledTraveller]

[bluebus86]

[andrewtf]

We have them as our auxiliary batteries in both Big Emma and Murphy.

One reason is that we could get larger batteries (physical size) because AGM batteries can be stored on their side. This makes connections and everything else .............. easier.
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'75 Riviera - 'BIG EMMA' (Pan American highway trip paused for a make over)
'77 Riviera - Murphy' (being reborn.... slowly)
'63 Austin Healey

[Abscate]

[Q-Dog]

I installed this AGM battery into my buggy because it is shorter/smaller and lighter than the stock VW group 42 battery I was using. My battery box has been shortened and the stock battery is too tall to fit.

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Brian

'69 Dune Buggy
'69 Beetle Convertible
'70 Beetle

[ImAddicted]

[rugblaster]

My daughter drives a E350 Mercedes Benz and it has had 2 AGM batteries installed by the dealer in Fort Worth in as many years. I'm 250 miles away so they have us by the short hairs. The second one they put in was a few months out of warranty. That is about $800 worth of AGMs in two years. I don't know if I'm a fan or not. My wife's car has one in it too, but it's mounted in the trunk. Also, I had to buy a smart charger to charge the fokker. (We're out of town for periods of time, sometimes.)
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[WhirledTraveller]

[andrewtf]

[heimlich]

Did you roll Big Emma back over? Give her an enema!


I have all Optima batteries and one Walmart lead battery. The Walmart battery is $25. It's lasted over 2 years and still going. Now I ask myself if the optima are worth it.
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[ImAddicted]

[heimlich]

[skills@eurocarsplus]

batteries are ALL junk these days. the claim to fame for the AGM's is a "cleaner" voltage so lots of high end shit use them. even still, you're lucky to get 3-5 years out of most (in high end cars, that is)

buy the biggest, cheapest battery you can stuff in the slot and call it a day. I just had to replace the battery in my blazah (that's right, bla-zah) plow truck. it lasted me 11 years.

the exact same battery I replaced it with must have weighed 5 pounds less. point being....they don't make them like they use to.

AGM isn't needed unless you have a special need for one. i'd save my money
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[Clatter]

[bnam]

The AGM in my 2008 E-class was only replaced in 2018. I think constant use is better for that battery. The lead acid in my Beetle was replaced in 2012. Still using it. I drive the car only 1000mi/yr or less.
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1971 1302LS Convertible (RHD) owned since '74
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