I didn’t do a ton of research into which batteries to buy for the truck. Instead, I visited Napa Auto Parts and got a quick brain dump on what to look for. They didn’t actual stock the batteries he recommend but I left with a plan to order deep cycle gel batteries.
Gel batteries are completely sealed, so they require no maintenance and can be mounted on their side, which gives us some flexibility. Deep cycle batteries are able to provide continuous power for a long period of time, even down to 20% charge. This allows you to run more electronics without impacting your ability to start the engine.
The current batteries had a Cold Crank Amps (CCA) rating of 780A, so I contacted Optima via their website to get the right model number and got a reply in a few hours. They recommended their Yellowtop D31a which exceeded the specs of the original batteries, rated at 900 CCA.
Batteries are heavy, so unsurprisingly Amazon had the cheapest price when factoring in delivery.