Spend 400 bucks for dual alternators on new Ram build?

[new2this44]

Hello. I am building a Arctic Fox 990 and a Ram to pull it. Is it worth building my ram with dual alternators so as to more efficiently charge my camper while driving?? Or will such a set-up require all new wiring, etc. to actually help?

Thank you.

[ksss]

I have ordered pickups with two alt. this last one I did not. I think it would help if you were doing a lot of winch work, or some other big draw application. Snow plow prep packages tend to spec a larger alt, but not the two alt option that I have seen. I would get the larger single alt and call it a day.

[travelnutz]

The thread OP is from/living in the Midwest where solar is very iffy at best and there's trees everywhere too which virtually block out the sun's rays anyway. Note that the promotors of solar are from the desert/bleak/virtually treeless areas of North America. We know the difference as that's where we live in the Midwest also and very smartly opted for dual alternators on our ordered diesel truck and been so happy we did.

Remember that the alternator works equally fast in recharging in any area/location you might be in unlike with iffy solar. Alternators are not affected by cold, altitude, clouds or trees, rain or snow, and is very fast and dependable.

It's not only the fact that the dual alternators will quickly when at engine idle recharge all the batteries (2 in the truck and 3 group 31 batteries for the Lance TC with its 1500 watt inverter or our Carriage 5th wheel with 5 same batteries in it and 2 more in the bed of the truck for powering the 5th wheel with its 2500 watt inverter). Even if in direct sun for 12 ours a day everyday, solar would be about like using a candle to heat a home in zero degree weather. Basically useless!

The additional plus is that having dual alternators and buying the extra serpentine single alternator belt stored under the seat means even if an alternator fails, you simply change belts and are good to go with the other alternator. A real game changer!

$400 seems a very high price for a second alternator as ours was well less than half of that cost.

[Cummins12V98]

I have towed for 30+ hours and my refrigerator was exactly the same temp at destination as departure. I have the 220A on my RAM.

[valhalla360]

time2roll wrote:
I would spend the $400 on solar or a DC-DC charger long before a second alternator.

Another alternative is swap out lights and oter devices to lower draw versions.

[time2roll]

I would spend the $400 on solar or a DC-DC charger long before a second alternator.

[Lwiddis]

“Most flooded batteries should be charged at no more than the "C/8" rate for any sustained period. While some battery manufacturers state a higher maximum charge rate, such as C/3, higher charge rates can result in high battery temperatures and/or excessive bubbling and loss of liquid. ("C/8" is the battery capacity at the 20-hour rate divided by 8. For a 220 AH battery, this would equal 26 Amps.)“ Northern Arizona Wind & Sun https://www.solar-electric.com/learning-center/deep-cycle-battery-faq.html/#Battery%20Charging

[NRALIFR]

GeoBoy wrote:
If you don’t have solar installed get it installed. Great way to keep the batteries charged while traveling.

Solar is good until the sun sets. You can also harvest more amp-hours from the truck than any solar install on a TC roof. One of the reasons I chose the Redarc DC-DC charger is because it has a built-in MPPT solar controller, and the unit will always take as much power from the Solar input as it can before supplementing that power, up to the maximum rated output, from Vehicle power input. Best of both worlds.

:):)

[Me_Again]

220 Single Alt, is just fine. Wasn't that many years ago that we had 45-55 Amp Alts.

[GeoBoy]

If you don’t have solar installed get it installed. Great way to keep the batteries charged while traveling.

[NRALIFR]

Arctic Fox 990 is a truck camper, so it’s hauled, not pulled like a trailer.

If you truly want to “more efficiently charge my camper while driving”, you’d be way better off putting a DC-DC charger in the TC as close to the camper battery as possible, rather than trying to do it with the truck’s alternator and bigger wires alone. I have no experience with dual alternators, but if the alternator is connected to the truck’s starting batteries, they are always going to base their output on the state of charge of those because they are closer to them. If they’re close to fully charged, and the camper batteries are lower, the camper batteries aren’t going to charge very well.

If you want to actually charge up your camper batteries as close to 100% as possible, Read This.

DC-DC chargers will also require heavier charging wires, but not as heavy as you’d need to get better charging using just the alternator alone. My install called for 6 gauge wires, but I had already installed 4 gauge wires and was disappointed with the results using just the alternator.

There are other brands of DC-DC chargers than the one I used (Redarc). CTEK and Renogy just off the top of my head. Renogy just recently came out with some very attractively priced units that I wish had been available when I bought mine. I’d love to see someone on here “Guinea Pig” one of them for us! :W

:):)

[Lwiddis]

“and it’s more than sufficient to quickly charge both batteries.“

You can try to throw lots and lots of amps at a battery but during the absorption phrase (80/85% to 100% full) the battery will only accept a diminishing amount and its takes time.

[Artum_Snowbird]

I would say 95% of the time you will be much better off with upgrading your wiring to No 8 wires or even No 6. The true reason you would want to do this is only if you don't have solar power, and you like to travel only for a couple hours. Larger wires will feed that engine power to your battery charger (usually a 45 amp per hour charger) and an average day camping will often consume 45 amps. But remaining at the No 12 feeds from your engine, will likely require about three hours driving instead of about one with bigger wires. It's not often that a single alternator would not provide that much power above all other needs.

[camp-n-family]

I went with the larger 220amp alternator option. It’s only a $50 upgrade from the factory and it’s more than sufficient to quickly charge both batteries.