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Dual battery mod

generalpetres

Full Member
Joined
Apr 21, 2007
Messages
95
I have only purchased the secondary battery tray so far but will be getting the painless 40120 dual battery kit soon and installing it on my truck
Here is a simple write up on what you will need to install the secondary battery tray.

Items Required;
Tray: gm part 15246518 price: 33.50
screw: gm part 1150853 price: 1.11
retainer: gm part 14005061price: 4.59
total cost: 39.20

Time took about 10 min, no rush goes on easy.

Tools:
sockets: 10mm and 13mm
ratchet



Here is the spot where we are going to be installing the new battery tray


Heres what the trey looks like, part numbers for it are at the top of this post including dealer pricing:



Once you have your sockets your going to want to remove the fender supports using the 13mm socket. once the brace is removed you will remove the 4 nuts from the bolts on the firewall with the same 13mm socket. after you remove the nuts you will then need to remove 2 bolts and a nut and move the radiator overflow bottle out of the way.
remove the bolt and the nut using the 10mm socket.


then on the other side of the overflow reservoir there is a 10mm bolt


once you remove the bolts and nuts slide the reservoir up and set it off to the side so you can remove the old plate and install the new batter tray,

once you have the tray in position reinstall all hardware and tighten down.

If you installed everything correctly it should now look like this.


I will continue to update this thread once i purchase the other parts necessary to finish this mod.

The part number for the dual battery kit i will be installing is Painless 40120 which doesnt require a switch to be mounted in the truck as the controller will automatically switch the battery for you.
You can order it from jeep 4x4center for 175 including free shipping.
digital-power-manager-40120_3233.jpg

http://www.jeep4x4center.com/painless-performance-digital-power-manager-40120.html?utm_source=google&utm_medium=productfeed&utm_campaign=cse&gclid=CPL1h4La6L0CFYqIfgod0hYAIw


I haven't decided on what battery i want to purchase for the secondary spot but im going to want to keep the fender brace in so this will limit the options on what battery will be able to fit in this location as clearance is a big issue.
 
I think the only size battery that will fit under the brace is a group 48.
 
Will you be wiring the batteries at the negative cables from primary battery to second battery or a separate ground for each battery cable?
 
i will more than likely ground each battery separately, this will reduce the amount of wires in the engine bay but also help keep one bad ground from affecting both batteries.
 
generalpetres said:
i will more than likely ground each battery separately, this will reduce the amount of wires in the engine bay but also help keep one bad ground from affecting both batteries.

That's the way to do it. Keep the ground wire as short as possible.
 
Yea, when you do it that way you increase the cranking amperage for the starter. Especially good in real cold temps.
 
I am watching this thread too...

I just bought the tray and installed it in my truck.. Still debating on what wiring setup I want to do. I have seen a painless wiring setup available for just over $100 but it is just the wiring. It did not say where the wiring went to.

I am assuming the ground can just go to the engine block. I have seen mention that there is an unused hole for a bolt for this use.

I am curious where the best place is to run the wiring to. I have seen people mention running it to the starter then putting the solenoid or battery cutoff near the aux battery.

Two things about the aux battery tray...
Looked like there was a hole on the side that would be great for mounting a solenoid to. It looked like it was a hole for pushing a wire harness mount to.

When I mounted my battery tray the hold down bolt hole is right under one of the access ports for the A/C line that you can see the picture of in this thread. In my truck it was lined up right over the hole. I am curious if this is an issue or if you can bend the tubing or something without damaging it.

At this point I have ONLY mounted the tray in place. I have seen others have left the bracing in tact above the mount. I should look at one of our work trucks that have this setup in it...

Anyhow. Suggestions?

Rodney
 
I kept it simple. The Positive side of my Aux battery runs to a simple on/off switch mounted on my firewall that passes to the starter/battery junction box near the alternator. Ran the Negative Aux battery cable to the engine block and firewall.

http://www.amazon.com/Marinco-701-Battery-Disconnect-Switch/dp/B005DUUL9W
 
I have been looking into doing this on my 2013.  Does any one know if the 2013's have an extra battery tray already installed?  Because mine sure looks like it.
 
Don't know - but if your plate looks something like
tray_zpsabe99ef8.jpg

The two "prong" things in a line (top of tray in pic) keeps the battery from sliding.
The two "prong" things at a 45? angle with the bolt hole (bottom of tray in pic) are for the hold down wedge and bolt.

If your tray has those features then you can drop a battery right in there. The hold down pieces can be picked up just about anywhere they sell batteries.
 
I have everything I need but the battery and wiring at this point...

I will be using my secondary battery to supply power to the interior of the vehicle for my computer and audio equipment. I recently purchased a pass-thru stud that I like better than cutting a hole and adding a Grommet.

I purchased a PAC-200 battery isolator which is a 200 amp batter isolation solenoid.

Now I need a good suggestion on where to mount this solenoid and where to get the ignition lead to turn on the solenoid when the truck is running. I am thinking of mounting the solenoid to the battery tray.

I will probably get 1/0 battery cables from http://custombatterycables.com and have them setup similarly.

The ground will be a side mount cable and will have 2 leads with one going to the engine block and the other going to one of the bracket mounting bolts on the firewall.

The +12 cable will also have 2 leads with one going to my pass-thru stud and the other snaking across the top of the engine block under the cover to the red alternator block on the front drivers side of the engine as someone else has mentioned. Modification of the block will be needed to accept the wire. Although I don't need such a big wire from that area it does reduce the chance of voltage drop. I may upgrade the standard battery cables and the alternator cable as well.

So other then all of this, again, does anyone have a suggestion of where to pull the switched lead under the hood to switch my solenoid?

Thanks! Rodney
 
Do we know for sure what type of battery fits under the brace? I looked at a battery last night that was too tall.

Was I believe a type 75.

Rodney
 
Nope the 75 will not fit under it, group 48 will. I just removed the brace years ago.
 
For best results run one ground to the engine block and the other to the frame. You should already have a ground strap from the engine to the body. If not run a smaller gauge or ground strap, you don't need a 1/0 to the body...
 
I am looking for a side mount battery that will fit in this location. I noticed the type 48 is a top mount battery.

I would like to keep the mounts away from the battery terminals and keep it looking factory.

I looked at my girlfriends 2013 Silverado and I believe hers is a type 48 and it is a top mount battery but they have some additional protection stuff on top of the battery to keep it from contacting the brace.

I am looking at this chart and it looks confusing to me... From this chart the Type 75/78 battery looks to be shorter but longer than the 42/48 batteries so I am not sure if the sizing is right?

http://www.batteryweb.com/bci.cfm

Looking at this one because it does point out side mount batterys.

I am in process of installing my second battery stuff but I didn't realize the battery it's self was so expensive.
I have a PAC-200 solenoid mounted to the battery tray. I plan to use 4 gauge for now and go over the top of the engine to the alternator connection. I will likely upgrade to 1/0 gauge wiring from custombattery.com at some point but 4 gauge should be OK for now.

I have a firewall pass-thru stud I am trying to find a good spot to drill through. The intention of this stud is to allow me to wire 1/0 wire to it from the engine compartment. I can then run 1/0 gauge wiring in the interior of the truck to the rear without having to use a grommet. I can also tap off this stud for my Computer equipment and any other additional equipment without much effort.

Going to try the passenger side later today...

Rodney
 
I used a side battery adapter for the primary battery it's top post because I did not want to change the stock cables. I've never had good luck with side post because they kept backing out from vibrations. Can't tell ya about other sizes you may have to measure. The top post has more options with cable connections.
 
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