Just curious about the dual battery dual alternators....

If you choose the dual batteries option on a 7.3 build, you automatically get the dual alternators.
I know that dual batteries would be useful if you live in cold climates, but why the dual alternators?
The std 240A alt should be plenty to keep two batteries charged up,

Would like to hear from those who have the dual alternators and have found a good use for them.

Thanks

 

$315 MSRP for dual batteries and alternators. Why ask why, just check the box and write the check.

 

I have the dual batteries/alternator on my 2020. I ordered it that way because i have a Lance truck camper and the refrigerator is a three way, so I can run it on 12volt. The 12 volt draw is enormous so having the dual alternators comes in real handy.

 

Ok, that makes sense.

Do you know if the dual alternators also includes larger gauge wiring to the 7-pin connector to support a higher rate of charge to the trailer/camper?

 

Sorry, I don't know if the gauge is heavier, but I doubt it. I ran a separate 8 gauge wire from the battery to a new Anderson Power Pole plug that I installed near the front of the bed. Works very well.

 

I don't believe both run at once from what I have read. I too have dual batteries/alternators. I believe 2nd is on idle most of the time until needed. I have an RV with solar and residential fridge along with other appliances that draw off the inverter/batteries. It's reassuring to know that I have the extra charging power when needed..... Hope this helps.

 

I had a long list of reasons to get dual batteries and alternators, but to answer your question(s)

1. The dual batteries require you to get dual alternators, Total cost IIRC about $315
2. To my knowledge, the wiring back to the trailer plug(s) remains unchanged from Ford.
3. The Larger alternator, 240 amps is primary and runs all the time. The smaller 157 amp runs as the system demands it to quickly recharge batteries or carry heavy electrical load for the snow plow guys and all that.

The only drawback I can see is the extra cost of replacing both batteries when the time comes and you need to replace both. You'd think your MTBF would be increased with dual batteries and alternators. We'll see. Troubleshooting a dual alternator system may be above my pay grade.

I was pondering the damage low batteries can do to starters. I bet dual batteries extends starter life.

 

Thanks all for the thoughtful replies.

While researching the subject of dual alternators, I found a bulletin from Ford with info pertaining to upgrading from a single alternator to a dual setup (and vise-versa).
Though not exactly related to this thread, it does contain good info for those of us who are interested in such things.
https://madocumentupload.marketingas...61dfa&v5=False

 

Another draw back is how packed it is under the hood. harder to access things.

 

Maybe if you want to install a supercharger.

 

Mine came off the lot that way but I pull a camper and I plow snow so I would have ordered the option if I did custom order my truck. For the minimal cost I would have never said no...

 

Plow, winch, lights, reserve capacity, $315…… sold

 

I was under the impression that on the newer SD trucks, when you upgrade to the dual batteries, it upgrades the single alternator to a higher output one. Not adding another one for a total of two. The dual alternators was on the older trucks.

I could be wrong but for some reason that is what I was thinking.

Edit: Never mind. “Dual alternators, 397 amp”. Awesome. I have no idea where I got the impression it was just a single upgraded one. Carry on

 

If you order the 6.2 with dual battery you just get a single 240 alternator.

 

I keep going back and forth on my build with that. Since I am using it for pulling a 5th wheel I was thinking it would be great for a dc to dc charger. On the other hand it adds more expense now and every battery change, two alts to go bad instead of one and most importantly its going to take 100 or so pounds off the payload.
So still dont know