Don't have an optima in the T but use two yellow tops in my Fourby running driving/camp lights, fridge, winch, diff locks etc. 150k over 5 yrs on some rough tracks and only replaced one a month ago after forgetting to turn off the fridge and not running the trucks for a week 😂. Normally after a good charge these things would revive but this was once too often; RIP old yella' I have heard any AGM battery needs a hefty voltage (14.4+) over a decent period to keep it at peak otherwise they tend to charge lower than 100%. Not a technician but heard some Prado owners boost the volts to the battery; as the engine heats up the alt reduces the volts below that needed to float AGM type batteries.