How to charge Ram Diesel batteries since there are two?

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lobsterbake

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Hello

I just picked up my Ram Laramie Diesel and would like to charge the batteries. How do you do this safely as there are two? The manual really doesn’t address and only says to disconnect the battery terminals if using a “fast” charger which I wouldn’t use. I just don’t know how to accomplish safely and really dont want to disconnect terminals, etc.

Any help is appreciated.

Thanks,

Mark
 

G. Mcpherson

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Curious as to why you need to charge the batteries that are new.
 
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lobsterbake

lobsterbake

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I want to make sure are well charged for longevity and might have not been adequately charged from factory.
 

BWL

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Just hook up 1 like normal and they'll equalize. The alternator charges the batteries pretty quick so unless there's a problem or the truck is sitting a long time there shouldn't be a need to charge them.
 

McBroom

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I would invest into a good battery maintainer if the truck is going to be sitting for long periods of time. Harbor Freight Tools carries a really good selection.
The maintain the batteries by charging as needed. It comes with an install kit that wires into a battery then you plug it into a 120V outlet. When it’s plugged up it’ll keep the battery charged and ready to go.
Note: the batteries must be fully charged prior to or it will not work properly.
Most have a quick connect
I prefer the one that has a short 120V cord that can be placed through the grille opening similar to the block heater plug.
Most also have charge level indicator leds. The maintainer controller can be mounted in the engine bay. fc523b57548614b8973ebdb7aecd0bb0.jpg0a2a1e7f28b7aea04f69c9a220adcd3e.jpg


I Love my 18 Ram 2500HD 4x4 CC
Blue Streak Pearl off-road package
 
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WilliamS

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unless its sitting thats the alternators job, you can use a trickle charger maintain them. As well they should be connected in parallel so you should only have to charge on one or the other.
 

Pricejh

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I’ve had my ‘15 2500 w/6.7l for 30,000 miles. Never needed to charge the batteries. It sits in the driveway for weeks at a time and gets started rarely. .


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Demon-HeMi

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each battery should be isolated, so hook up the battery like you would any other battery charger and charge one at a time, same concept as using a diesel to jump a gas engine, you hook up only one battery because its 12v, the truck has the system to take the 12v from each battery and turn it into 24v where needed while not letting it back-feed the 24v back to the 12v battery
 

crash68

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each battery should be isolated, so hook up the battery like you would any other battery charger and charge one at a time, same concept as using a diesel to jump a gas engine, you hook up only one battery because its 12v, the truck has the system to take the 12v from each battery and turn it into 24v where needed while not letting it back-feed the 24v back to the 12v battery

Ram CTD are only 12V systems, both batteries are wired in parallel with each other. That why you have to replace both batteries at the same time and need to be identical.
Medium duty/over the road semi trucks use a 24V system, primarily for starting.
 

PNW-Ram

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each battery should be isolated, so hook up the battery like you would any other battery charger and charge one at a time, same concept as using a diesel to jump a gas engine, you hook up only one battery because its 12v, the truck has the system to take the 12v from each battery and turn it into 24v where needed while not letting it back-feed the 24v back to the 12v battery

The CTD Ram trucks are 12v, not 24.

If you need to charge, simply connect a battery charger to one of the batteries and plug it in. The batteries are linked, and will charge (or drain) together as if it were 1 large 12v battery.

It's very straightforward. And I'll echo the comments that say it's probably not needed. The Diesel trucks have a 180 or 220 amp alternator (some trucks have two of each). Since you were able to start the truck on the dealer lot and drove it home, you're fine. If you plan to let it sit for months at a time, I'd consider a battery tender (trickle charger), especially as the batteries get older.
 

WilliamS

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Ram CTD are only 12V systems, both batteries are wired in parallel with each other. That why you have to replace both batteries at the same time and need to be identical.
Medium duty/over the road semi trucks use a 24V system, primarily for starting.

The CTD Ram trucks are 12v, not 24.

If you need to charge, simply connect a battery charger to one of the batteries and plug it in. The batteries are linked, and will charge (or drain) together as if it were 1 large 12v battery.

It's very straightforward. And I'll echo the comments that say it's probably not needed. The Diesel trucks have a 180 or 220 amp alternator (some trucks have two of each). Since you were able to start the truck on the dealer lot and drove it home, you're fine. If you plan to let it sit for months at a time, I'd consider a battery tender (trickle charger), especially as the batteries get older.

So is my statement correct, a trickle on either battery would tend to both of them correct?
 

dan212

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Batteries usually come charged. Whatever the gap is, driving around a bit should do the trick. My truck sat for 4 months an started up like a champ. But 6 years later the batteries couldn't hold a charge. They all do age out. Went to autozone and bought two enormous replacement batteries (not cheap). They came charged and I happily drove home.

Translation: Don't worry about it.

Hello

I just picked up my Ram Laramie Diesel and would like to charge the batteries. How do you do this safely as there are two? The manual really doesn’t address and only says to disconnect the battery terminals if using a “fast” charger which I wouldn’t use. I just don’t know how to accomplish safely and really dont want to disconnect terminals, etc.

Any help is appreciated.

Thanks,

Mark
 

G. Mcpherson

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I think the general consensus is...... Don't worry about it.
 

SyN

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I have used the Noco Genius G750 since day one on my new 2017.
My ram normally sits for 4 to 14 days without being drove.
During that time I normally have the driver side battery (plugged in) which has a Permanent Noco connection attached to it—Just plug it in.

Normally within 8-12 hours both batteries are fully charged.
Winter time it is really a plus.
Even though she spends most her time in the garage (not out in the elements 24/7).

CB2F2A3E-65B5-468D-800A-8622303EC812.jpeg

Got the idea from a relative: Whom uses the same set up.
This seems to extend battery life. If I can get 2-3 more years out of both batteries it will be $$$ well spent. Even though the G750 is not that expensive.

EA082018-BA00-44AB-8123-96C400A59911.jpeg

I have Noco connections like this on both batteries but connecting the G750 to the drivers side battery seems to charge the passengers side as well. I’ve been told the drives side battery carries more of the load.
My relative has a Noco set up that routes both plugs through the front of the grill to where he does not have to open the hood.

This is the unit I have mounted on the other side of the garage for the wifes car. (Normally only use it during the winter months) even though I will find time to connect it overnight occasionally during the summer.

NOCO Genius G1100 6V/12V 1.1A... https://www.amazon.com/dp/B004LX3AXQ?ref=yo_pop_ma_swf
 
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lobsterbake

lobsterbake

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I bought a Battery Tender Plus and it is a 1.25A 12V charger and I hooked the positive to the battery terminal on the drivers side battery and the negative to a metal part of the engine. It took about 13 hours to charge the drivers and then I disconnected and did passenger side and it took about 8 hours to get to 100% charge on that battery. The passenger side had the red charging light and green light flashing which meant the battery was at 80% but still took a number of hours to go solid green. You can see where I hooked to the metal (right of label in pic) for the driver side battery. I used the round hook that is used to lift engine out of vehicle when charging passenger side. On drivers side - wasnt sure if could use the bolt on top of metal plate I chose to hook to as not bare steel and used the steel below. I assume this is ok to use.

CD308A27-DAA7-4096-89A1-01969B584CBB.jpeg
 
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Jimmy07

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If you plan to let it sit for months at a time, I'd consider a battery tender (trickle charger), especially as the batteries get older.
Just to clarify. If leaving the truck sit for months, you would use a battery tender, not a trickle charger. A battery tender knows when the battery is fully charged and automatically stops itself from charging until needed. A trickle charger doesn’t know when to stop so it will eventually keep overcharging.
 

mtofell

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Here's a story that may be a bit off point but I'll share anyway. A buddy and I camp together with our RVs each year. Both trailers are less than 5 years old. When storing them at home he's always worried about over-charging so he constantly unplugs and plugs in his trailer and uses various battery tenders and chargers. I never do a damn thing other than leave my trailer plugged in. EVERY year his batteries die and he's running a generator constantly and talking about getting new batteries.... again. Mine are 3+ years old and we just finished a trip. I ran my generator once midweek for a couple hours just because I figured I should. They worked flawlessly.

Again, maybe a bit off point but sometimes it's best to just leave things alone and let the engineers that designed the things have their way.
 
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