Off-Grid Engineering Dual Battery System Q&A

No problem at all. None of those are dumb questions.

Your 2006 TRD-Sport will require a special side-by-side tray that is not available on my website... yet. I spent a lot of time today completely redesigning my side-by-side trays. The "universal tray" may just go away... as most folks were using them for Tacomas anyway. The 2nd Gen Tacoma side-by-side trays will be available on my website sometime next week. They are available for purchase right now by emailing me.

The 2nd Gen Tacomas don't leave much room for turning the batteries sideways up in that corner. So, the tray was designed to hold 2 Group 35 AGM batteries. A Group 34 is simply too long and will not fit behind the headlight.

With proper installation of the side-by-side tray, access to the oil filter is not entirely impeded. You will still be able to get the filter off.

I would be happy to make any custom cables you need. This includes a "Big 3" upgrade or custom fuse box cables. Simply let me know the exact lengths of each cable and I can advise you on the recommended AWG and then quote you a price. Im pretty reasonable with my custom cables... as Im usually building them all day anyway.

Thanks for your interest and let me know if you have nay more questions.

 

Thanks for the quick response time!

So... If I'm understanding what you're saying correctly, I can just remove my driver side headlight, and all will be good. Motorcycles are fine with just one, so I should be too I reckon.

I went out and took a picture of my current set up (yes my engine bay is very dirty, and yes that is most certainly a piece of wood as a spacer for the hold down ). The big cable coming off the right side of the positive terminal is for my winch, and off the left goes into my aux fuse block.


It looks to me like there is more space towards the inside (engine) than the outside (fender). Would it be possible to mount my current battery on the engine side, and a group 35 odyssey battery on the fender side? Looking at the battery dimensions, the 34 is actually slightly narrower than the 35, so that might help as well. I know that matching battery size is important, but I was under the impression that the ML-ACR can compensate for slight differences. Am I mis-interpreting that?

Thanks again!

 

Subbed!

Been running @HeliMedic kits for about a year now! Very happy with it no problems.

 

Ha! Yep, the headlight delete mod will definitely give you the additional room. Might as well run a Group 31 at that point.

You are correct abut there being more room on the engine side of things. There are still two problems with running your Group 34 battery on that side. One, the tray has a tab on the front of it, that is specifically designed to keep the battery from sliding forward. This tab could be removed if desired, but of course not recommended. Two, the Group 34 is quite a bit shorter than the Group 35. The tiedown would not be able to secure that battery unless it was the same height as the 35. You could make a spacer for it to solve this.

The ML-ACR does not necessarily "compensate" for any difference in battery size, but technically thats ok. Blue Sea recommends matching the batteries as close as possible but is perfectly ok with small variances.

 

Wow! Very helpful post.

Upon further reading, it seems to me that, in a system where the batteries are only linked during charging, the size doesn't matter so much as the type of battery. As long as they require the same amount of voltage to charge, they should be fine. In a permanently linked system (no isolator) it is necessary to have the exact same battery if you want any sort of life expectancy out of your batteries. Please correct me if I'm wrong!

I don't want to make you say that this is possible for any sort of liability reasons, but from what I gather, it is! haha

My ghetto rush job of a spacer (that I said I would make something better about 8 months ago) has held up fine over many thousands of kilometres of off-road adventures, in a mount (stock) that is far too large for my current battery, so I think that a spacer in your properly sized tray would work totally fine.

The only point of concern would be removing the tab. I am confident that the battery wouldn't move (although it's not ideal) without it, but I am thinking I could probably fab something up that would hold it in place if it became a problem.

I know that all of this might go against the grain of conventional wisdom, but to me it seems like an awesome set up, using the 35 as the starter battery, then the 34 as the AUX with it's extra capacity, and fitting as much battery as possible in that very limited area. Again, I could be totally wrong. Later down the road, when the batteries eventually die, I could replace them with the exact same battery, and all would be good again (apart from the missing tab). I am running lights, a fridge, a winch, and a compressor off of my starter battery, and it's starting to make me a little nervous on our more "out there" solo excursions, even though the Odyssey 34 has never skipped a beat yet, even with running lights and the fridge for a few days without starting the truck (no solar).

Maybe I will take a measuring tape out and see what's what in there. or even disconnect my battery and see if it would fit.

If I did decide to do this, it would obviously require some slightly more custom wiring. I guess that wouldn't be a problem for you?

As a side note, I've been looking into getting dual batteries pretty heavily for a while now, and your trays, and kits are the best I've seen. I was planning on building everything myself, but your kits just look so polished that I want it! though my engine bay will never ever be as clean as your pictures! haha! I only wish that it was possible for me to have the split setup, and none of this would even be an issue.

 

hey @WormSquirts your funny and i give you +2 internet points for making me laugh. I hope it'll fit there. good luck man, @HeliMedic is a good dude and will take care of you if he can!

 

Thanks Coop! Glad your system is treating you well!

 

You are absolutely correct. The construction type is the number one consideration. Size is number two. Age and general condition being number three.... if I had to put them in order.

Running a Group 34 in parallel with a Group 35 may not be as ideal as two Group 35's, but it should work fine. At the moment, Im personally running a Group 31 as my auxiliary battery and a Group 35 as my starting battery (contrary to the advice I give regularly). To combat a possible chronic undercharge condition, I simply isolate my batteries and place them each on a charger every now and then. I also have a 100 watt solar panel that keeps my auxiliary battery topped off and then shares the charge with the main battery. It is a setup that I personally designed knowing all the possible downfalls. The way my kits are setup and recommended to be utilized is way more reliable.

With all that being said, I feel that your Group 34/ Group 35 setup will treat you well if you are willing to make the modifications necessary to make it work. I would be happy to work with you on any custom wiring you may need, as well.

I really appreciate the compliments on my systems. I really do work around the clock on these setups to make sure that Im delivering the best products I can.

 

Haha thanks Rock Ninja!

That's awesome! I am about to head out camping in the snow for the weekend, but I will definitely be sending you a PM or Email next week about pricing etc. I do have a price cap, but I don't think it should be too much of an obstacle!

 

Aww shucks

Thanks man!

 

Very cool. Enjoy your trip. Shoot me an email when you're ready.

 

To isolate the two batteries you are locking off the ML-ACR, correct?, next can you leave all cable connections on the battery posts? and then connect one charger to each battery? I can read the above to mean you disconnect each battery from all cable prior to connecting a charger.
I like the solar panel aspect.

 

To isolate the batteries, the ML-ACR gives you two choices. Simply flip the in cab switch to the "off" position or pop the hood and manually place the relay in the off position by turning the yellow knob to "lock off". The former is obviously the easiest and the latter is for the paranoid that want to know that the batteries physically can not connect, under any circumstances.

There is no need to ever remove the battery cables, unless you need to physically remove the batteries from the vehicle.

 

I have a kt on order,was wondering where folks have mounted the in cab monitoring unit.....tnx in advance


Just a follow on..ordered 2 PC1400/35 from Battery mart..great price..free shipping (crazy huh) were on back order, they told me they would ship on the 30th (they did) got them on the 31st..snow and all..




....very nice folks and good service

added both toys.......

 

I have mine mounted in the center console. The switch rarely needs to be accessed and doesn't need to be in plain sight. Some people have modified a switch blank to allow fitment of the slightly bigger ACR switch. Depending on your particular truck, you may not have any blank switches to work with. In that case, Im a a big fan of the center console.

 

He says you don't in the other thread.

 

Its all good. @ramonortiz55 was just trying to help. And technically, we're both right. If you go with the recommended batteries and pay attention to the placement of the tray when installing, you will have plenty of clearance to remove the oil filter. If you must install larger batteries, you may not.

 

Oh yeah all good, I just wish I didn't have that stupid ABS booster in my way on the passenger side.

 

Me too! I much prefer the split system. But stay tuned... the side-by-side is about to get a whole lot nicer

 

@HeliMedic, email sent via website! looking forward to your amazing split dual battery system!