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Passing on some info about second battery option.

64BAwagon
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64BAwagon Senior Enthusiast

64BAwagon

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Posted

I opted for the 2nd battery ($135) along with the 220a alternator ($150) on my 2024 3500 L8T gas truck. When I got it I noted that there were a couple of relays on the side of the battery as well as a bus bar and fuses on the top. It was much more than just another battery connected to the main one. I was told yesterday that the components on the 2nd battery are actually part of whats included in the plow package. The system will sense a large power draw from something like a hydraulic pump on the plow and then puts the alternator into a full output mode rather than shutting it off when the battery is charged and the load is low. This apparently prevents the system from having large loads placed on it when its in low consumption mode. 

I bought this option because this truck is used mostly for towing and I wanted extra capacity since the trailer increases the 12v demand. For the money it was a worthwhile option but now I have the added value if/when I sell it and it can easily be used for a plow truck. (it also has the "camper" heavier front torsion bars)

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64BAwagon
64BAwagon

I opted for the 2nd battery ($135) along with the 220a alternator ($150) on my 2024 3500 L8T gas truck. When I got it I noted that there were a couple of relays on the side of the battery as well as a

Another JR
Another JR

Part of the assembly that comes on top of the second battery in a gas truck is a battery isolator. Loads you connect to the aux battery are isolated from the starting battery when the truck isn’t runn

Another JR
Another JR

To answer your question for yourself, you need to have a good understanding of the wiring and the way the isolator works. So here’s some  additional clarification.   I created confusion by usin

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kf9yr Enthusiast

kf9yr

Posted
Posted

If you buy part # 84669070 it comes with the fuses that connect to the bus as well as the fasteners that are fit for the 2nd battery tray.

 

Makes it easy to connect high amperage cables.

 

 

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Dunn Senior Enthusiast

Dunn

Posted
Posted

Well worth the money....if I ordered one 100% I would get it, I usually buy off the lot and rarely do you find them

Ausslo Enthusiast

Ausslo

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Posted
On 9/18/2023 at 12:35 PM, kf9yr said:

If you buy part # 84669070 it comes with the fuses that connect to the bus as well as the fasteners that are fit for the 2nd battery tray.

 

Makes it easy to connect high amperage cables.

 

 

That kit is actually a plug and play for the primary fuse block though you could use it on the auxiliary block with some modifications. I just installed it on mine.

  • Like 1
Another JR Senior Enthusiast

Another JR

Posted
Posted

Part of the assembly that comes on top of the second battery in a gas truck is a battery isolator. Loads you connect to the aux battery are isolated from the starting battery when the truck isn’t running so they won’t deplete your starting battery. This is different from the diesel, which has the batteries directly connected at all times because they both are needed for starting. 

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Ausslo Enthusiast

Ausslo

Posted
Posted
On 9/20/2023 at 3:50 PM, Ausslo said:

That kit is actually a plug and play for the primary fuse block though you could use it on the auxiliary block with some modifications. I just installed it on mine.

FusePanelPic.thumb.jpg.cbaba6d1da451005b6c95c1cba211ed7.jpg

GMC4Zee Enthusiast

GMC4Zee

Posted
Posted

I have plow option but be aware that it also includes the striffer front springs which does affect the ride somewhat. I did get the dual batteries also.Harness was included with the option.

  • 1 year later...
revrnd Senior Enthusiast

revrnd

Posted
Posted
On 9/20/2023 at 10:29 PM, Another JR said:

Part of the assembly that comes on top of the second battery in a gas truck is a battery isolator. Loads you connect to the aux battery are isolated from the starting battery when the truck isn’t running so they won’t deplete your starting battery. This is different from the diesel, which has the batteries directly connected at all times because they both are needed for starting. 

 

That's what my brother & I have been trying to figure out since I got my 2024 L8T w/o the plow prep. I've had 5 gassers GMT400 & up w/ the VYU, but none of them had an auxiliary battery.

revrnd Senior Enthusiast

revrnd

Posted
Posted
On 9/25/2023 at 9:14 AM, GMC4Zee said:

I have plow option but be aware that it also includes the striffer front springs which does affect the ride somewhat. I did get the dual batteries also.Harness was included with the option.

 

Having been around 3/4 tons since the 70s, I hadn't really noticed the stiffer front suspension on them. Seldom have I driven a 1/2 ton. I have driven my brother's 3/4 ton Dmaxes, that is a different story though.

T Slave Enthusiast

T Slave

Posted
Posted

I ordered my 2022 with 2nd battery plow truck package, thought it was a great buy for extra battery and 220 amp charging system. I put the front 10,000 lbs. receiver hitch on the front to be able to put my winch in and made a bull bar with lights to go in when winch is not being used. Installed quick connect plug like on fork truck battery chargers on truck and winch. Just load the winch in receiver plug into truck and ready to use. I have a 13,500 lbs. winch pulls great. Though one day I might get one of them Home Plows for the driveway in the winter. It's got a stiffer front suspension than my older 1 ton had but not all that bad. 

  • Like 1
gemarsh Senior Enthusiast

gemarsh

Posted
Posted
12 hours ago, T Slave said:

I ordered my 2022 with 2nd battery plow truck package, thought it was a great buy for extra battery and 220 amp charging system. I put the front 10,000 lbs. receiver hitch on the front to be able to put my winch in and made a bull bar with lights to go in when winch is not being used. Installed quick connect plug like on fork truck battery chargers on truck and winch. Just load the winch in receiver plug into truck and ready to use. I have a 13,500 lbs. winch pulls great. Though one day I might get one of them Home Plows for the driveway in the winter. It's got a stiffer front suspension than my older 1 ton had but not all that bad. 

I'd love to see the bull bar setup!

  • 3 weeks later...
3500L8T New Member

3500L8T

Posted
Posted (edited)

I have the same factory option dual battery in my 2021 Silverado 3500 Gas L8T. I would like to know if there is any isolation between the two batteries so that when the auxiliary battery starts to drain it does not affect the first battery. Or do both batteries just charge and discharge equally with no protection in between?

Edited by 3500L8T
Another JR Senior Enthusiast

Another JR

Posted
Posted
26 minutes ago, 3500L8T said:

I have the same factory option dual battery in my 2021 Silverado 3500 Gas L8T. I would like to know if there is any isolation between the two batteries so that when the auxiliary battery starts to drain it does not affect the first battery. Or do both batteries just charge and discharge equally with no protection in between?

See my September 20 post up above in this string. Yes there is an isolator. I have a 2021 3500 gas truck with dual batteries and 220 amp alternator. 

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