Shops with diagnostic equipment (Jiffy Lube, etc.) could probably give you that answer.

You probably have an 80-amp unit if you found a salvage unit that is more powerful than the original.

I suppose the alternator responds to load requirements, and therefore would not put a constant 80-amp load unless necessary. After all, the regulator tries to maintain a steady voltage, so the amp load would have to vary according to demand.

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2009 ML350 (106K) - Family vehicle
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