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Dual battery/alternator configuration?

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I’ve got a 2021 Silverado 3500 on order with the Duramax engine and it includes the dual battery and dual alternator option.  I’m wondering what advantage this setup offers besides the obvious redundancy.  Can one battery be isolated to support only specified circuit(s)?  I’ll be towing a large 5th wheel RV and am wondering how to make best use of this setup.


Thanks in advance for any information you can provide.

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Since you have the Duramax, GM automatically puts in dual batteries, hooked in parallel, to provide the power needed to start the engine.  Neither is on an isolator.


The dual alternators are to provide more power while the engine is running, for, say, running a plow, a more powerful stereo system, charging rv batteries up, running a more powerful inverter, etc.

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