Great question!
My speculation is that the alternator does what it can. I can’t remember what the amperage of the stock alternator is. And at some point they switched to a higher amperage alternator. They may have gone from 140a to 160a or something like that. I think the battery takes care of the rest. Check what the cranking amps are on the battery. It’s usually marked.
This is what the battery in the X says.
This is a spare that I pulled from the Frontier before I turned it in. I may add it as a second battery in the X at some point, but I have an identical one in it now.
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