I have a good AGM in my partner's 2001 Jeep XJ (the top model from O'reilly, which is the same manufacturer as Interstate AGM batteries), but the alternator in that vehicle doesn't properly charge it (the battery always reads low with a volt meter). After doing some research about the proper charge voltage (higher than the charge voltage for an old-style flooded lead acid) and float voltage (lower than the charge voltage for an old-style flooded lead acid) for AGM batteries, I elected to put two regular old Interstate flooded lead acid batteries from Costco into my 80 series. The AGM in the jeep seems to be holding up fine to the all-wrong voltages (it's in it's 4th year and still starts the jeep) but I figured it's better to match the batteries to the alternator and charging management system in the vehicle.The mission is important and the goal in sight. A relaxed approach does us good and gets us there sometimes faster. Replace the battery. Get a good AGM. It won’t be cheap.