So how do I actually get the most out of my AGM?

I'm finding all kinds of information on what I need to do to fully charge it, from "just get a tune and tell them you have an AGM" to "hook it up to a trickle charger once a month" to "upgrade your alternator because you need more amps than the stock one can provide to fully charge it"

So what's the word? I don't want to get stuck on 80% and I'd like to avoid spending money on things I don't need.

I just ordered:

https://www.napaonline.com/en/p/ODYODPAGM27F

First of all, is that a "very good battery" or is it wrong/bad for my application?

It'll be my only battery, and I'm mainly looking for something that will still start the car after I leave my door open for 30 minutes. My OEM 2017 24F is starting to run into issues. I know an AGM is overkill for what I do, but I'd like to have the lowest chance of running into issues.

 

The Odyssey 27F you linked is pretty much the top battery you can get. The parent company EnerSys now owns Odyssey, Northstar, and X2 brands. They are more or less all the same thing and great batteries.

You don't need a bigger alternator unless there are other factors. But to properly charge it on a 3rd gen you either need a tune to increase the alternator output amperage max (AGM takes more than lead acid), or just trickle charge once a month as you already mentioned. Trickle chargers are cheap, tunes are not. The best answer for your case depends on your goals for the truck and I can't tell you that because I'm not psychic. Even if you do neither of these things the battery will probably last at least the 3 years covered under warranty and probably much longer.

 

I don’t run an AGM, but I have yet to see any proof that upping the charge voltage via a tune really does any added good. Seems like those who don’t do so still have fine battery life. I haven’t researched it in a while but that’s what I gathered a while back when I was searching to see if people were addressing via tune or not and how it was going as a result.

 

Says it on the battery, I am not an electrical engineer or a chemist so I follow it.

 

I know what the battery and the specs say to do. I am not ignoring those. I fully believe the best way to charge an AGM is doing so how the manufacturer says to.

What I don't believe, is that doing what we do to simply raise the voltage, is what the battery wants. Based on that pic you posted, the battery would want the voltage to be altered between cycle service and float. Tunes on a 3rd gen or anything else on any other gen isn't correcting the process, its simply raising the voltage across the board. Which still isn't what the battery says it wants.

They do vary the voltage some across temps, such as when the engine heats up, the voltage is dropping bit by bit. But I still doubt it's near as good as using an actual AGM charger which charges the battery exactly as it wants to be charged.