2021 E450 dual alternator

Per the Magnuson–Moss Warranty Act, adding aftermarket equipment (including what would be the factory dual alternator setup if so equipped) won't legally affect the vehicle warranty unless Ford can show that the added equipment caused the problem. Of course, the aftermarket bits themselves also aren't covered by the standard vehicle warranty.

The law doesn't stop unscrupulous dealers and companies from attempting to get out of warranty work, but the legal requirements are pretty clear. They aren't allowed to say "You installed a second alternator, therefore we're denying warranty coverage on your failed windshield wiper arm" or whatever.

brianjw wrote:
It was the Ford dealer parts dept, they’ve historically been awful.

I’m not concerned about warranty, the second alternator wouldn’t be integrated into factory electronics at all. I’ve modified everything I’ve ever owned.

I’m going to run a 400 amp hour lithium battery setup. I want to be able to run the roof top AC off of the Victron inverter while driving (or just quickly recharge the batteries while driving). The plan is to run a 60 amp sterling B2B charger off of each alternator, for a combined 120 amps to the lithium battery bank. I don’t want to overwork/overheat a smaller single alternator asking too much from it, and this seems like the safest way to do it. A little overkill, sure. No, I don’t want to have to rely on the generator while I’m driving. In fact if the solar and alternator perform well enough the generator will come out.

I regularly charge my E450 motorhome's 230 AH AGM coach battery bank by idling it's V10 to spin the stock 130 amp alternator. Since AGM batteries also charge faster than liquid acid batteries, this idling charge method only takes a relatively short time. HOWEVER - I do wish that I had dual alternators for critical equipment redundancy!

pnichols wrote:
Let me chime in here with some thoughts:

1. Large and reliable alternators will probably become more important as lithium coach batteries become more common in motorhomes. Supposedly lithium battery banks charge fast - but only if one has a charging method that can deliver the high currents that the batteries will accept. For dry camping - especially when many hours of enough solar aren't available - a large capacity alternator driven by an idling chassis engine might be very useful.

2. Since any vehicle's alternator is very important, having two on board - when one or the other is getting used a lot for high current lithium coach battery charging year after year - to me would be a necessity for equipment backup purposes should one or the other fail when drycamping. Always have a Plan B for critical Plan A failures!

P.S. I think that emergency service vehicles often have dual alternators.

Exactly this, thank you. Most ambulances around here are privately owned ragged out rigs. The company I work for has switched to a lot of transits for new rigs (or HD commercial trucks) so I haven’t seen new 7.3L gas ambulances around here yet. Maybe I need to head over to a ford truck forum and see if I can find a VIN that works.

It was the Ford dealer parts dept, they’ve historically been awful.

I’m not concerned about warranty, the second alternator wouldn’t be integrated into factory electronics at all. I’ve modified everything I’ve ever owned.

I’m going to run a 400 amp hour lithium battery setup. I want to be able to run the roof top AC off of the Victron inverter while driving (or just quickly recharge the batteries while driving). The plan is to run a 60 amp sterling B2B charger off of each alternator, for a combined 120 amps to the lithium battery bank. I don’t want to overwork/overheat a smaller single alternator asking too much from it, and this seems like the safest way to do it. A little overkill, sure. No, I don’t want to have to rely on the generator while I’m driving. In fact if the solar and alternator perform well enough the generator will come out.

Let me chime in here with some thoughts:

1. Large and reliable alternators will probably become more important as lithium coach batteries become more common in motorhomes. Supposedly lithium battery banks charge fast - but only if one has a charging method that can deliver the high currents that the batteries will accept. For dry camping - especially when many hours of enough solar aren't available - a large capacity alternator driven by an idling chassis engine might be very useful.

2. Since any vehicle's alternator is very important, having two on board - when one or the other is getting used a lot for high current lithium coach battery charging year after year - to me would be a necessity for equipment backup purposes should one or the other fail when drycamping. Always have a Plan B for critical Plan A failures!

P.S. I think that emergency service vehicles often have dual alternators.

What "parts" store were you at? Autozone or Advance are likely clueless. NAPA or Federated would likely be a bit more helpful. The Ford dealer parts department would likely be your best choice.
I too would check with Ford on possible warranty complications.
What are you going to be running with the extra power? 210 amps is huge in the world of automotive alternators.

theoldwizard1 wrote:
Curious. Why do you think you need dual alternators ?

X-2

Is it a good idea to do this while the brand new rv is still under warranty ?

Curious. Why do you think you need dual alternators ?

You can find lots of info here.
You can also contact the Ford Upfitter team on there.

https://www.fordbbas.com/home/