Originally Posted by TX_TRU_STUD
So from what yall are saying, I can just pick a battery on my 6.7 and then connect it like normal to the old truck? Sounds good to me.
The 6.7's batteries are in series, correct? Not parallel?
It sounds like you have the right idea, but are using the wrong term.
A series circuit would require the negative terminal of the first battery to be hooked to the positive terminal of the second battery. This allows for only one path of electron flow, and doubles the system voltage, to 24V nominal.
A parallel circuit allows multiple paths of electron flow. The positive terminals of both batteries are hooked to the same source, and both negative terminals are to ground. This system keeps the voltage at 12V nominal.
Either way, long story short; the system should be a parallel 12V, and you can jump just like any other vehicle, from either battery.