Dual Battery Setups! Let's see them! Multiple Batteries Thread!

That's a good looking mount. I'm wanting to do something similar. Right now I just have a mess of wires and nothing permanently mounted. Did you have a shop make that for you? Or did you do that yourself?

 

I designed it and had a shop make it for me.

 

Thanks! Any possibility to get the drawing/dimensions of it? Might look at doing something similar and would be a good starting point. You mounted it to those two holds on the side right?

 

PM me.

 

I know this is in here somewhere, but I can't find it. What gauge wire are you guys running from the starting battery to the ML-ACR? I was planning to use 1/0. Is that sufficient?

 

1/0 is what I used

 

I am running the 1/0 cable to the bed for my second battery from the ML-ACR.

 

Another question, for those of you using the ML-ACR, why are some using the Isolation #1 brown wire and some not? And where are you hooking it up?

 

You don't need to use it. My understanding is it's a feature for boats where sometimes they crank the engines for extended periods before they start. The brown wire would keep the batteries isolated for 3 or 5 minutes after key on rather than 30 seconds

 

I hooked it up to the accessory in the fuse box.

 

You don't need it in the car. It too keep sensitive electronics from being exposed to high crank amps at startup.

 

You mean the fuse box under the hood, or in the cab?

 

Under the hood. I used a meter to find a switched power that I tapped into, wouldn't auto switch on and off without it.

 

Read all 48 pages!

I don't have any high power accessories. My reason for a 2nd battery is primarily as a backup system. I tend to off-road in the dez solo. I'm avoiding the high tech stuff and going simple and affordable. I've purchased everything but the battery.

I will be upgrading the wiring with two gauge except I got 1/0 gauge for the alternator wire. My first question pertains to the alt wiring. My 07 Taco has a four gauge wire from the alternator to the fuse box. Wire bolts on 8mm bolt on engine end of the box. From same end below the box is a six or eight gauge wire that goes to the battery. This wire does not appear to be easily replaced and not much is mentioned here on upgrading this wire. Has anyone replaced it? How? Are you guys bypassing it?

 

I read all 48 pages too!

No high powered accessories as well... until I get a winch. I need the backup system for your same reason, since I also to tend to go off-road solo... in the mountains (no desert here.) After looking at all the whiz bang gizmos and doodads and re-evaluating my complete electrical ineptness, I will also trying to avoid the high tech stuff and go simple and affordable. I haven't acquired the battery as well, because i haven't figured out where to locate the 2nd battery, as I've heard varying opinions on this thread. I think I'll locate the second battery in the passenger side space in the engine bay. Not sure yet.

I will however, likely go with the Stage 1 kit that @BamaToy1997 offers, since it appears to be a simple and complete solution and I think it deals with all the wires that you have mentioned. The options for a second battery isolation system is also offered by Bama when I need it later.

Good luck with your install... post up your progress if you can.

Thanks.

 

I'm not sure if I understand exactly what you're talking about, but if you're referring to the small, short wire from the positive battery terminal into the under-hood fuse panel I can say that almost none of us replace or bypass it. There's a couple reasons:
1. If you're not connecting high draw items to the existing internal or external stock fuse panels it's unnecessary to replace it because there's no more draw than normal
2. It's a pain in the ass to get to and replace
3. We hook up auxiliary blue sea fuse panels directly to the battery and run extra equipment off those.
4. <s>That wire isn't part of the charging system so won't affect the efficiency at all<s> edit: in the stock harness, the wire from alternator output does route through the fuse panel. apologies.

Bottom line is that there is no reason I know of to replace it or bypass it. The wire is plenty big to run all of the stock electronics for the truck.

 

Yes, that wire, but I disagree with #4, that wire is what charges the battery (on my 07; could be diff on other model years). I find it counterintuitive to upgrade all the wiring except that one. I eventually plan on replacing my alt with a 200 amp model; so, I'll be looking to upgrade that wire by replacing it or adding a jumper wire. What I picture doing is running a two gauge wire from alt to relay; a two gauge wire from relay to fuse box, replacing the current four gauge wire. Then, either running a two gauge wire from relay to battery, or from the fuse box to battery. I may leave the short wire alone because I don't know what else may be under the fuse box to it.

I'm putting together my own upgrade kit. Below is what I've gathered so far (everything purchased on Amazon):
Temco two gauge wiring. $32 for 10' each of black and red housing. Battery wiring.
Crimp Supply 1/0 wiring. $23 for 10' of red housing. Alt and starter wiring.
200 watt Cole Hersee solenoid relay #24213. $37.
Best Choice 10-ton crimper. $48. (looks identical to other 10-ton crimpers with diff labels.)
Fastronix military type battery connectors. The $31 kit for one battery and $7 x2 solo connectors for the other.
Wirthco metal battery tray. $13.
DROK cigarette lighter volt meters. $8 x2. Already had these, but added them for reference.
Scoshe fuse holder and Install Bay 500 watt ANL fuses. $23 (fuses come in 10-pack).
Add crimps, on/off switch, split wire looms and shrink tubing.

Future purchase: 200 watt alternator from BNR Parts, an eBay vendor. $195. ($215 for 250 watt model.) Free shipping. They have a 99.9% positive rating and a feedback score of 11209; so, I think they are worth the inherent risk. Plus, their warehouse is a two hour drive from me.

Here is a pic of my installed battery tray. Used mending brace, L bracket, and washers to level it. Had to get rid of air duct - may have to replace when getting smog inspection. Top spacing is barely 8 inches; my group 24 battery fits but terminals are too close for comfort with hood clearance. Will likely use group 34 battery.

 

I apologize, my mistake I forgot how the original setup was from the factory. You will replace the alternator to fuse panel wire and run that straight from the alt to the battery. Then you can leave that little, short 4 gauge wire connected from the battery to the fuse panel and it doesn't need an upgrade if you do it that way.

Then there will be 2 factory wires connected to the battery that don't need upgrading. They are positive terminal to starter solenoid and positive terminal to fuse panel. Those 2 are not part of the charging system.

 

Since there are only two wires connected to the battery post and one goes to the starter, it stands to reason the smaller wire, the one to the fuse panel, is what carries current to charge the battery. Now, I haven't taken the harness apart, are you saying the starter wire has a connection to the to the alt? From a quick inspection last weekend, it didn't appear that way. I found a youtube video showing how to replace the alt fuse; it's under the fuse panel and it appears the short wire connects to one end of it - the same end but at the bottom of the bolt, out of view, where the alt wire comes into the fuse box. I'm gonna take the panel apart this weekend and see if I can replace that short wire with two gauge, unless I can see the alt connects to the starter wire. https://www.youtube.com/watch?v=LO9UgFbt1tY&index=2&list=WL