Diesel auxiliary battery shots, placement & removal.

[staying_tuned]

I apologize for any redundancy in the info I'm posting. I'm in need of relocating my auxiliary battery on my diesel and wasn't able to find any photos or intel on the tray placement vs. the gasser. I knew, based on previously removing the wheel liner, the layout was different. The bad news is that unlike the gasser our auxiliary battery cannot be removed or serviced by removing the fender and liner. The fantastic news is that unlike the gasser, ours is located (and easily accessed) by simply removing the primary battery. This makes an aux swap a 15 minute job max.

I'll post relo shots along the way. if I can find a compatible lithium swap to save space I'll likely mount it high up in the passenger footwell. If not, likely down the frame near the rear wheel.

Pics below.

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[A 2]

Why do you need to replace the Aux battery? Did it go bad?

Edit: you said relocating not replacing. Any thoughts on relocating both batteries to lighten the front end load and more air circulating space under the hood?

 

[Mr._Bill]

This is the ESS battery, not a auxiliary battery for accessories. Its primary purpose is to keep the computers stable during ESS events. Trying to relocate it can have unknown consequences. If you want a true auxiliary battery, mount one and connect it using a Smart Isolator. There is space for a battery box on the frame behind the right rear wheel.

 

[The Crusader]

Why do you need to move the battery? Are you looking for a larger battery for camping?

I'd get a larger lithium battery to mount in the back and parallel it with your little battery with a solenoid to isolate the new battery when the accessories are turned off. Attach any solar charging to the new battery. Some charge controllers can also charge your starter battery secondarily. You could even include an Anderson connector and only install the new battery when you go camping . Include a switch to turn off the solenoid when the new battery is removed.

Did you have another reason for moving the little battery? I could be getting ahead of myself .

 

[staying_tuned]

Relocating for a few reasons, all would likely be considered absurd by most. The most pressing & annoying is the passenger side Falcon 3.1 shock. Without going into the whole story, a few weeks back the Falcon primary website mentioned no compatibility issues on the 3.1 with the diesel. The vendor, upon my double-checking also visited the same page (literally) and confirmed no issue. I purchased them. Turns out, that was a fail.

Falcon agreed to offer an RMA and has since updated the site but the diesel variants have an unknown ETA, minimum is 6 months. They confirmed valving setup is near identical but for diesel they reduced the length of the reservoir. I could go with another shock setup entirely but that leads me to the below.

While vendors like Evo offer Aux/ESS relo kits specifically for the diesel, it is meant to compliment their full coil-over kit. The relo box mounts to their coil-over bridge directly. Like Falcon, their diesel coil-over kit isn't valved drastically different, sensibly, it is the springs that differ. Super slick but not much help to those that don't plan on a coil-over conversion.

Third, if I want to be in a position to expand/scale the system for increased load, I would like to abstract and isolate it and hey if it addresses my immediate issue why not.

Lastly, at this point it's a matter of principle. The aftermarket is bending over backwards to fabricate niche solutions to problems revolving around the placement of this battery (Genesis, again with no committed ETA on dual-battery for diesel. Their published date of October should not be considered reliable per Mike at Genesis as of 72 hours ago and while they did confirm this battery will not exist, they couldn't confirm if they'd be utilizing its space or not as part of their diesel-centric design). I want to move my particular situation towards something more conducive to having variety & flexibility like I would with the gasser. I absolutely love my diesel JT which is why I'd even consider doing something so admittedly illogical : o ).

Ok, that ended up taking more words than planned but there you have it.

 

[staying_tuned]

This is the ESS battery, not a auxiliary battery for accessories. Its primary purpose is to keep the computers stable during ESS events. Trying to relocate it can have unknown consequences. If you want a true auxiliary battery, mount one and connect it using a Smart Isolator. There is space for a battery box on the frame behind the right rear wheel.

Can you confirm that the ESS battery never (assuming stock wiring/setup) serves the role of cranking the motor outside of alerting the starter that it's time, at which point the primary handles that load? I ask because the amperage & wire reqs jump significantly if so. Essentially a 4' run would need 4/0 to start the truck, where-as I could easily get away with straight 4 awg otherwise based on the data I've gathered and load reqs vs. run length calculations.

 

[Mr._Bill]

Can you confirm that the ESS battery never (assuming stock wiring/setup) serves the role of cranking the motor outside of alerting the starter that it's time, at which point the primary handles that load? I ask because the amperage & wire reqs jump significantly if so. Essentially a 4' run would need 4/0 to start the truck, where-as I could easily get away with straight 4 awg otherwise based on the data I've gathered and load reqs vs. run length calculations.

The primary purpose is to keep the computers stable. I don't know if it is used for anything else. The size of the cables and capacity of the battery would lead me to believe that is not part of the design.

I installed a third battery for accessories. It is connected using a Smart Isolator, and mounted to the frame behind the right rear wheel. I left the ESS battery and factory wiring intact.

 

[staying_tuned]

The primary purpose is to keep the computers stable. I don't know if it is used for anything else. The size of the cables and capacity of the battery would lead me to believe that is not part of the design.

I installed a third battery for accessories. It is connected using a Smart Isolator, and mounted to the frame behind the right rear wheel. I left the ESS battery and factory wiring intact.

Good deal, I’ve read the posts covering your install a few times, excellent information. I’m going to go 4/0 to be safe and plan to just coil it up and let it sit in the passenger footwell for a few weeks to ensure its stable over as many ESS events as possible. I quite like the location you’ve suggested and opted for yourself. I’ll likely reuse the cutout from the lower tray. Given the hatch lid I hope to pull the tray entirely and cut the lower portion away to repurpose as the box for the rear. There is enough wiggle room in the box to allow me to mount it directly to the unused holes in the rear with some low profile bolts. I can likely shim inside and outside with large washers at a minimum to reinforce the mounting points.

 

[kevman65]

I've not seen under the hood of a diesel JT to know the real estate, but it's probably possible to make a "floating" tray to set the AUX battery.

This goes back to my earlier motorcycle days, but we used to "engineer" a battery out tray to maximize under seat storage area.

 

[staying_tuned]

Staged the ESS battery under the rear pass seat, fits great. Over the coming weeks I’ll push it back behind the rear all together but wanted an easy way to monitor it. Terminals at ESS battery are rubber wrapped for now, will flux down and heat shrink on final stage. Ground to chassis, 1/0 SGT runs.

Falcon 3.1 fits like a glove now, finally. Zero errors or odd behavior, will try to initiate as many ESS events as possible.

 

[staying_tuned]

Happy to report that I’ve had 7 auto stop -> start events since the relo. No abnormal behavior at all. Anthony from Falcon said this is the first documented usage of their full sized piggy-backs on the diesel. All other stubborn idiots who’d do the same, it seems as though zero side effects so far. I’ll list full parts list but in short, Morris fully insulated butt connectors for the 2x 6 awg to my 1/0 splice. Terminated existing ground. Then down at the rear cab on the battery, two screw clamp copper terminals (posts are M6). New chassis ground at rear seat mount -> dialectic greased with patch of rubber sound deadened over it all, also SGT 1/0 wire.

Wiring is secure and finished in rubber wrap with super 88 (Morris butt connectors are marine grade/full rubber outside) up front while just rubber wrap out back. As mentioned before, I’ll clean up the back with heat shrink, wanted to ensure no anomalies before buttoning it up.

 

[Pescatoral Pursuit]

I'm having the same problem now. If only I could order the diesel shocks but they're 6 mos out according to falcon and everyone appears sold out.

I'm curious in all your research, and given that I don't use the ESS feature, is there a smaller battery out there that will perform the basic duty, and allow the falcon reservoir to share the same space?
Or can it simply be deleted somehow?

 

[staying_tuned]

I'm having the same problem now. If only I could order the diesel shocks but they're 6 mos out according to falcon and everyone appears sold out.

I'm curious in all your research, and given that I don't use the ESS feature, is there a smaller battery out there that will perform the basic duty, and allow the falcon reservoir to share the same space?
Or can it simply be deleted somehow?

Not that I’m aware of. I do know that Genesis will eventually drop their dual battery setup for the EcoD but it was already supposed to be out by now. Delete seemed too fraught with electrical gremlins. It has been done but way too complex for me to feel confident DIY. Would have loved to find a baby AGM or lipo but again fraught from my perspective. Relo was just more about being time consuming and using good wire. If I had to start from scratch, it could be done in a few hours for sure. I cased it out like 10 times as if I were some type of bank robber or something because of all the mythical properties this aux battery has on the internet. EOD it’s a battery that wasn’t in a great place for me, so I moved it. Feels like forever ago but zero hiccups etc.

If you do this, make sure you don’t allow the aux battery to ground even after disconnecting the main or it will pop a fuse and don’t waste time cutting a shape out. I forgot the aux lid itself is part of the primary’s base. Cut the whole tray out. I plan to go back and use the recovered space for an arb single.

 

[Mac Attack]

Not that I’m aware of. I do know that Genesis will eventually drop their dual battery setup for the EcoD but it was already supposed to be out by now. Delete seemed too fraught with electrical gremlins. It has been done but way too complex for me to feel confident DIY. Would have loved to find a baby AGM or lipo but again fraught from my perspective. Relo was just more about being time consuming and using good wire. If I had to start from scratch, it could be done in a few hours for sure. I cased it out like 10 times as if I were some type of bank robber or something because of all the mythical properties this aux battery has on the internet. EOD it’s a battery that wasn’t in a great place for me, so I moved it. Feels like forever ago but zero hiccups etc.

If you do this, make sure you don’t allow the aux battery to ground even after disconnecting the main or it will pop a fuse and don’t waste time cutting a sharp out. I forgot the aux lid itself is part of the primary’s base. Cut the whole tray out. I plan to go back and use the recovered space for an arb single.

Will love to see how you do that!

 

[Pescatoral Pursuit]

Okay, do I decided to relocate the auxillary battery next to the main by cheating it closer to the firewall and it makes just enough room.

The problem I'm having is a spark when I go to connect the loose ground that attaches to the negative post.
Is there that much draw just sitting there? It does it whether the aux battery is wired or not.

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