2 Amp Maintainer for Stored Duramax Dual Batteries

[Rene T]

When I go to Fl this winter, my truck will be parked in my garage. I have the Dura Max diesel. It has two batteries hooked in parallel.
I want to keep them charged. I also have a battery maintainer. It is a NOCO GENIUS2- 2 Amp. I know that if I connect the charger just to one of the batteries, it will also maintain the other one at the same time.
I’m just wondering if this small maintainer is big enough.
NOCO also have a 5 amp and a 10 amp. Should I be getting one of them or it the 2 Amp big enough to do what I want. The batteries are only a couple of years old.

 

[DonTom]

When I go to Fl this winter, my truck will be parked in my garage. I have the Dura Max diesel. It has two batteries hooked in parallel.
I want to keep them charged. I also have a battery maintainer. It is a NOCO GENIUS2- 2 Amp. I know that if I connect the charger just to one of the batteries, it will also maintain the other one at the same time.
I’m just wondering if this small maintainer is big enough.
NOCO also have a 5 amp and a 10 amp. Should I be getting one of them or it the 2 Amp big enough to do what I want. The batteries are only a couple of years old.

Yes, it will be one amp to each battery. It will keep the charge just fine for when you're not using the rig.

But it probably will not charge a well discharged battery, but if the batteries are already fairly charged up, it will work well to keep the charge.

-Don- Baker, NV

 

[Mark_K5LXP]

The unknown is what the vehicle is drawing sitting there. Disconnecting them plus using the maintainer removes all doubt that vehicle draw, power loss or maintainer failure won't create a bad day.

Mark B.
Albuquerque, NM

 

[bigbAZ]

Typical parasitic load on a 2011 Duramax is under 0.050 amps once everything goes to sleep so you should be good. Just be sure to keep the key fobs far enough away from the truck to let the wireless module go to sleep (some have motion detection but I wouldn't count on it).

I have also read that locking the doors helps because it puts things into a deep sleep mode.

 

[Rene T]

Typical parasitic load on a 2011 Duramax is under 0.050 amps once everything goes to sleep so you should be good. Just be sure to keep the key fobs far enough away from the truck to let the wireless module go to sleep (some have motion detection but I wouldn't count on it).

I have also read that locking the doors helps because it puts things into a deep sleep mode.

Thank you everyone and I don’t have any key fobs.
I think what I may do is I’m also going to have my car in the garage. I may put that 2 Amp maintainer on the car and buy a 5 Amp for the truck just to be sure,

 

[Mark_K5LXP]

What happens if power is lost (breaker/GFI), the charger is unplugged (on purpose/accidently), or the charger fails? If someone's checking on it then you're OK. If you're expecting to come back months later it'd be a good idea to mitigate the risk. It's simple, no reason not to.

Mark B.
Albuquerque, NM

 

[RayIN]

FLA batteries have a self-discharge rate of approx. 3%/per month when disconnected. Why not simply disconnect the neg cables?
The 2A maintainer should work fine if you go that route.
I'd be more concerned about forgetting to top-off the fuel tank just before putting the truck into storage.
A side-note. One winter we stayed in FL for 6 months, when we returned DW's 2017 Grand Cherokee battery was dead. I forgot to attach the 2A battery maintainer. Can't disconnect that battery, it's under co-pilot seat. (original battery)

 

[Gary RV_Wizard]

LOL! Reading these well-intended replies, I can't help but think things like "way over-thinking" and "belt plus suspenders?". Seems like the worst that can happen is the minor nuisance of returning to a dead battery, and that's probably recoverable with several hours of slow charging.

 

[Mark_K5LXP]

If some inconvenience were the only consequence then the overkill seems OCD. Starting batteries especially are sensitive to deep discharges, and with all lead acid, the amount of time spent discharged. Runing a battery flat and immediately charging it there's a good chance it will come back. Run it flat and leave it that way for weeks much less months and you have doorstops. Even if charging is successful, their capacity and longevity will be significantly reduced. So I guess if the "suspender" part (charger) is considered overkill, at least do the "belt" and lift a cable, so the worst that happens is self discharge. Anymore batteries can be upwards of a couple hundred bucks, more than a consumable in my book. Throw in the distraction/inconvenience of the replacement task, I think is worth a bit of prevention.

How many stories are there on the forums from folks that discover their batteries are flat after their charger or converter was off during storage? It's so simple to migigate that, why not.

Mark B.
Albuquerque, NM

 

[Almost There]

Thank you everyone and I don’t have any key fobs.
I think what I may do is I’m also going to have my car in the garage. I may put that 2 Amp maintainer on the car and buy a 5 Amp for the truck just to be sure,

Rene, last winter I couldn’t head south due to getting a new knee.
I’m in Ontario and it was a long COLD winter.
My 2 batteries in my diesel wouldn’t start the truck after a couple of weeks sitting. Bought the small Noco and found it wasn’t going into maintenance mode. Possibly because of the batteries still being connected and outside, not sure.
I bought the 10 A maintainer and it worked like a charm. Many times I checked and found it was maintaining vs charging.

Hope this helps.

 

[glenn_c13]

When I go to Fl this winter, my truck will be parked in my garage. I have the Dura Max diesel. It has two batteries hooked in parallel.
I want to keep them charged. I also have a battery maintainer. It is a NOCO GENIUS2- 2 Amp. I know that if I connect the charger just to one of the batteries, it will also maintain the other one at the same time.
I’m just wondering if this small maintainer is big enough.
NOCO also have a 5 amp and a 10 amp. Should I be getting one of them or it the 2 Amp big enough to do what I want. The batteries are only a couple of years old.

What I do is I hook up a solar charger. 100 watt panel and a solar charge controller. It works great in Michigan.

 

[Rene T]

Rene, last winter I couldn’t head south due to getting a new knee.
I’m in Ontario and it was a long COLD winter.
My 2 batteries in my diesel wouldn’t start the truck after a couple of weeks sitting. Bought the small Noco and found it wasn’t going into maintenance mode. Possibly because of the batteries still being connected and outside, not sure.
I bought the 10 A maintainer and it worked like a charm. Many times I checked and found it was maintaining vs charging.

Hope this helps.

It just so happens that my 5Amp NOCO maintainer came in today from Amazon. I’ll use this one in the truck with dual batteries and the 2Amp will be for my car. This year we purchased a used Subaru and we are going to drive it to FL and leave it there then fly back and forth. I’ll probably buy a 2 Amp maintainer for that car.