GMC trucks and SUVs are heavy on electricity. A V8 Yukon or Sierra has to turn a big engine, then run rear AC, cooled seats, screens and power steps, often while idling outside a school or a tower lobby. Older models use a conventional flooded or calcium battery. Newer ones with automatic stop-start leave the factory with an AGM battery and must get AGM again, or stop-start quits and the new battery fades early.
On the Yukon and Sierra the battery is under the bonnet. Recent GMC models have a battery sensor on the negative cable. It does not usually need coding, but it has to be reconnected correctly and the car left locked for a few hours to learn the new battery. A memory saver keeps radio presets, seat memory and window settings in place during the swap. The first-generation Acadia is the odd one out, with its battery under the cabin floor behind the front passenger seat.