Upgrade the starting power in your 2011-2016 Chevy/GMC 6.6L LML Duramax with a new battery. Dual batteries were offered on some heavy-duty diesel trucks. If your truck has two batteries, it's always a good idea to replace them both at the same time. Shop XDP today and get a new battery for your vehicle. XDP carries leading battery manufacturers such as Odyssey, and more! A battery's average lifespan is normally between three and six years. Chemical reactions cause batteries to steadily degrade even under perfect conditions. Your truck's battery can fail and need to be replaced for a variety of reasons. The indications of a weak battery will often include slow engine cranking and dim or flickering headlights.