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Which Battery For Auxiliary In Gmt800 W/tp2?

Wayne02

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Wayne02 Enthusiast

Wayne02

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Truck: 2000 GMC 2500 SLT NBS with trailer package currently wired and in use with travel trailer.

 

Working on upgrading to the TP2 option which I believe is the factory aux battery wired such that it is isolated from the start battery. This is the install where the aux battery is located on the passenger side between the firewall and the coolant reservoir.

 

Desired operation: Aux battery factory wired to be isolated from the start battery. Aux battery will be used to power truck camper or travel trailer.

 

When at camp (truck immobile) the aux battery will be re-charged (topped up so as to not let the state of charge decline too much) daily using a 110V charger powered by my generator.

 

1) Given this application which battery should I source? Deep cycle, not used for starting, tight install location. For those of you who run this set-up, what battery are you using. What manufacturer/model? Is there a specific size of battery that will fit this application?

 

2) Would the need to recharge the battery each day favor a battery that has both side and top terminals such that the truck wiring cables are connected to the side terminals and I could us the top battery terminals to clip the battery charger leads to?

 

Would charging the aux battery daily via a 110 charger with leads hooked to aux battery terminals present any problem with damaging the trucks electronics? (I'd really rather not have to disconnect the cables from the battery each time I recharge it)

 

Thanks

dewfpo Senior Enthusiast

dewfpo

Posted
Posted
Truck: 2000 GMC 2500 SLT NBS with trailer package currently wired and in use with travel trailer.

 

Working on upgrading to the TP2 option which I believe is the factory aux battery wired such that it is isolated from the start battery. This is the install where the aux battery is located on the passenger side between the firewall and the coolant reservoir.

 

Desired operation: Aux battery factory wired to be isolated from the start battery. Aux battery will be used to power truck camper or travel trailer.

 

When at camp (truck immobile) the aux battery will be re-charged (topped up so as to not let the state of charge decline too much) daily using a 110V charger powered by my generator.

 

1) Given this application which battery should I source? Deep cycle, not used for starting, tight install location. For those of you who run this set-up, what battery are you using. What manufacturer/model? Is there a specific size of battery that will fit this application?

 

2) Would the need to recharge the battery each day favor a battery that has both side and top terminals such that the truck wiring cables are connected to the side terminals and I could us the top battery terminals to clip the battery charger leads to?

 

Would charging the aux battery daily via a 110 charger with leads hooked to aux battery terminals present any problem with damaging the trucks electronics? (I'd really rather not have to disconnect the cables from the battery each time I recharge it)

 

Thanks

 

 

I posted some photos and diagrams of the factory TP2 setup which I have on my 2005.

 

http://www.dieselplace.com/forum/showthrea...ight=dewfpo+tp2

 

From the factory, both of my batteries are exactly the same.

 

DEWFPO

Wayne02 Enthusiast

Wayne02

Posted
  • Author
Posted

Thanks DEWFPO, that's a nice looking installation.

 

I'm having a heck of a time finding a group 78 RV side terminal battery for that location. I need a deep cycle RV battery for the Aux battery, not another start battery like the primary battery in the truck.

 

Has anybody successfully squeezed a group 24 top terminal battery into this location?

 

I have all the parts ordered and on the way to put the factory second battery option into the truck. This includes all the battery cables, the isolator, etc. The cables are for a side terminal battery and I'm not finding many side terminal RV deep cycle batteries.

 

The option package is apparently sized for a group 78 battery which is the same size as the primary start battery, and a bit smaller than a group 24.

 

I went to the big battery store today and after some research and head scratching they said the Duracell group 78 AGM with side terminal option is the only "RV/Marine" side terminal battery they know of in that size and it was $200. I guess most RV/Marine batteries are top terminal.

 

I could maybe do a group 78 top terminal and use the top to side terminal adapters. This might open the options up to more than just Duracell.

 

I got the tray installed today and attempted to put a costco group 24 battery in there but it was a no go. I can cut the tab back that is coming off the cowl and that would give a little more room but I don't know if it will be enough. In the picture the battery is propped up on the right by the stud which the coolant reservoir mounts to and I need to slide the battery toward the firewall a couple of inches to get it to drop down inside of that stud. And if I do get it in there I don't know if it will be too tall. The other complicating factor is the AC line goes right alongside parallel the battery and prevents any movement towards the engine during installation.

 

881152843_RkCcT-L.jpg

 

881152887_SBg8t-L.jpg

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