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Dual Battery mod

SAPPER17

New Member
Joined
Jan 14, 2005
Messages
7
Location
Ft Hood Texas
I have bought the painless kit and 2nd battery and tray.  How do you tap into the wire coming from the main battery and where do you mount the solonoid and where should you tap in at the fuse blocks. thanks. I would like to finish it this weekend, just need to buy the wire at NAPA
 
I installed a dual battery system using a Hellroaring dual battery Isolator/Combiner.  Although they are not the same, I think the pictures here may me of some use. 
I put the BIC on the fire wall next to the battery tray.  There doesn't appear to be much behind it.  The tie in point was very easy.  Just use the little red box that ties the alternator to the main battery.  Some trimming will be necessary depending upon cable size.  I used 2 guage welding cable.

 

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As a follow up, I used aan opening bolt hole in  the front of the block as a grounding point.  I think it was a M12, but don't quote me.  I've slept since then....


The MOX
 

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SAPPER17 said:
Thanks for the Help. Does it matter if you ground it on an aluminum head?

I wouldn't think it would be a problem.  It has more than enough mass to make for a good conductor.  It might be smart to put a dielectric paste between the cable and the head.  But my experience is that copper and aluminum doesn't cause too much galavanic corrosion

 
Aluminum is an excellent conductor. The problem is the aluminum oxide that forms instantly in the open air, which isn't. And there's maintaining the tension of a connection, etc.
 
Where is there room for the 2nd batt?
I have an 04 2500 and can't find room
must be looking at it again
would be a help if you have any ideas

  Thanks bqblaz
 
bqblaz said:
Where is there room for the 2nd batt?
I have an 04 2500 and can't find room
must be looking at it again
would be a help if you have any ideas

? ?Thanks bqblaz

On the Passenger Side fender.  Towards the Hood hinges.

JW
 
I didn't think there was room because of the fender brace
Is there a certain size or brand that will fit under it

              bqblaz
 
bqblaz said:
I didn't think there was room because of the fender brace
Is there a certain size or brand that will fit under it

? ? ? ? ? ? ? bqblaz

I don't quite remember, but I know that is where it goes, my 2500 diesel had it there, and I know I've seen 2500 avalanches with it there too.

They make a bracket for it to sit on. I think it offsets it enough.


JW
 
The fender brace must be removed. The (If GM) bracket itself handles the bracing.
 
does anyone have a part # for the bracket
or does the oem one work?
 
I called my dealer and got #s
15705102  tray
15727997  bracket
I hope this is right. Ordered from gmpartsdirect.com

          bqblaz
 
bqblaz said:
I called my dealer and got #s
15705102  tray
15727997  bracket
I hope this is right. Ordered from gmpartsdirect.com

          bqblaz

from a thread "second battery tray" I copied this...what someone else used...

from chevy dealer get the passenger side tray, screw and battery clamp. respectivly the
Part numbers: 15705102, 11509853, and 356668


hope this helps...
 
Thanks for the #s web
I will order them
I had one right at least

    bqblaz
 
More info...

HTH also... :cautious:

http://www.chevyavalanchefanclub.com/cafcna/index.php?board=163;action=display;threadid=33308
 
My battery tray finally arrived. Long story, but it was gathered from another dealer as the one I ordered never showed. Bob really did me a favor getting it in time for the Xmas break.

tray.JPG


The second battery arrived today and I dropped it into place. I wired it to charge from an isolator-

isolator.JPG
isolator2.JPG


...and added my surplus Battery Brain as the method of combining them.

dualbat.JPG
dualbat2.JPG


I can manually combine them under the hood , or use the remotes. The way it is set up this battery charges when the truck is running. It remains full and fresh. When I need extra reserve I combine them and "jump start" myself. Fairly simple right now. We will see what the future brings.
 
I am wanting to run a dual battery setup and have one of them in the bed. I was just wondering if there would be a problem with gas build-up from charging the battery. I was also wondering if there is a benefit to running a red top/yellow top setup. I am running a yellow top right now and havent had any problems with it.
 
Just to update this. I made a couple changes.

KISS. I eliminated the Battery Brain and installed a Simple , inexpensive battery switch.

batteryswitch.JPG


Flip the switch to combine them. A simple as it gets.

My wife's car needed a battery so my aux. battery went to her car. I got a new matching Sears Diehard Platinum to replace it :)
 
Nice setup HenryJ yep sometimes simple is best. (y)
 
Does anyone here know what size battery group will work with the GM auxiliary battery tray? I can tell you that it's not an Odyssey 34/78 battery. It's too long.
 
I've had good luck with the Duralast batteries. I used Duralast Golds size 78 in my 2005 LT Z71. It fit the tray with the standard GM hold down block but had to modify the fender brace.
 

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