My 2012 6.7 is going to be sitting in the garage for a while and I want to put a trickle charger on it.

How do I hook up the positive and negative leads when the truck has two batteries?

Bruce

 

Just hook up to one it will charge both.

 

Interesting topic.
I always kept a weatherproof batteryminder mounted under the hood and attached to my 6.0 I rarely use my truck in the winter. Additionally I also would plug in the block heater a few hours before I knew I would be starting it.

I was afraid to connect the battery minder to my 6.7 last fall when I got the truck in the yard because of that big sticker threatening a warranty void for aftermarket parts under the hood

And after a few bitter cold New England mornings I noticed a few things about this truck.

-You do not need to use the block heater, seems to start smoothly in the cold.
Read the manual the temperture expectations are awfully low before Ford expects us to plug these in.
-I never saw the electrical system weaken on the 6.7 like the 6.0 did on a cold start. I plug a digital 12v gauge into my power port so when I walk by the truck I can observe the current battery state at a glance.
-The remote start worked flawlessly from the house

Could be those few issues from the 6.0 caused many of the FICM and injector issues we were pained with and did Ford recognize that improving the electrical system and cold starting power... you never know.

I am planning another winter without the battery minder.
It is down cellar waiting just in case it was that new truck first winter luck...

 

There is always a small amout of resistance in the cables between the batteries. This will cause a very small voltage drop to the battery not connected to the charger. While not a big deal, the very best way to connect the charger leads is connect the minus on one battery and the positive on the other.

 

I have a 6.0. Do the 6.7's have the same problem with ficm's if the voltage gets low??

 

I am hoping that awfull issue is behind us.

 

Couldn't a person disconnect the positive on one battery and then put a trickle charger on each battery for a more efficient trickle charge and desulfinating cycle?

 

You could also consider a dual bank charger/tender. They will charge batteries in series or in parallel. Ours are in parallel, but this charger will isolate each and charge/tend as needed. This seems like it would be better for the life of the battery if one is slightly weaker than the other. I use this charger/tender on my jet boat and I love it. I have often considered using it on my truck.

 

No FICM on the 6.7! The injection system doesn't sap power like the 6.0 does. There is no power draw to heat the inductive coils on the injectors, just small electrical pulses to tell the injector when to fire. The glow plugs are much more efficient now as well.

 

What he said.

I am also amazed how quickly this thing starts - admittedly I hardly see the temps that a lot of you do, but in comparison to my 7.3, the 6.7 starts instantaneously.

 

All you really need is a Battery Tender Junior...around $30 on Amazon. It will completely charge and maintain the batteries. I've had the same one on my 6.4 that I use on my 6.7L. Works very well.

 

My pull start lawn mower starts quicker than a 7.3. LOL

 

Thank goodness. My 6L kept burning those up if battery voltage was low, because they used a DC-DC step up converter and for the same amount of power with a lower voltage results in higher current.

 

This was my favorite perm mount under the hood charger. Still have it safely waiting just incase I need I again.

Power Tender Plus 12 Volt 5 Amp Waterproof Battery Charger - Free Shipping: BatteryMart.com