Dual Battery In My ‘18 Silverado

[xocyrusx]

I wanted to share this as i thought others may be interested in this... I’m sure there is mechanics here that have pros and cons to this but for the average Joe I am I took on the project...

All though this isn’t directly shooting relating, I did it for the all of the additional conveniences It provides me out at the range with out draining my starting battery. Would for sure apply to hunting and camping as well.

My range is deep in the middle of nowhere, all though a club most of the time I’m there by myself at the 1300 yard range. I drive my truck to each target down range so it’s as much of range tool as it is getting me to and from. Being from Florida heat and water are always a concern so be stranded sucks let alone 1.5 hours away from home.

Below are the reasons I wanted it as well adding a fuse box so I can easy add additional accessories.
- Truck Bed Outlet 12v & USB (Camping Refrigerator/Freezer for drinks and food for long days at the range and charging electronics while the truck is off)
- Truck bed Lighting (I get to the range early and now with Day Light Savings im fighting lighting)
- Ability to Jump Start Myself (Say No More)
- On Board Air to Clean Off Dust and Dirt
- Plus I’m sure other stuff I haven’t thought of

I have installed the Dual Battery already and installed the truck bed outlet and lighting. I switched up the panel in the bed to condense the USB and voltage meter and add a second switch for the bed lighting. The battery is on a relay that charges when the truck is running from the main battery but when it’s off it isolates it self from the main.

I won’t go into crazy detail here but I wanted to share as I think others may enjoy this project. Plus Silverado’s scream for this as they have a space for a second battery.

Any questions or suggestions please feel free to reach out...

 

[Powder_Burns]

Used to have a 2nd deep cycle battery in my old truck to run inverter, winch, and a water pump. I’d like to set up something like that again, one of those rainy day projects on the pile.

 

[Ravenworks]

Good idea to be prepared.

I'd like to suggest that you get some good quality military terminals.
They will offer a positive point of termination.
Trust me those wingnuts are not something that you want to rely on permanently.

Second get some covers on your terminals.

When using a dual setup both batteries should be identical.

 

[Winningdog]

Years ago a Friend tried this and his alternater couldn't keep both batteries charged. Newer trucks may not have the same problem.

 

[Sniperwannabee]

For jump starts I pack this : super small light weight jump box

https://www.amazon.com/Audew-20000mAh-Starter-Battery-Charging/dp/B07GR17R3X/ref=sr_1_1_sspa?crid=1OSA0K3LTE9PT&dchild=1&keywords=adew+jump+starter&qid=1604289766&s=automotive&sprefix=Audew%2Caps%2C1608&sr=1-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEyNFdJNzJOODNPTTJGJmVuY3J5cHRlZElkPUEwNTk4NjE3NlJPUlc2OERBSk1IJmVuY3J5cHRlZEFkSWQ9QTAwMzQ3Mjc0SU4xSThKOVNYUVAmd2lkZ2V0TmFtZT1zcF9hdGYmYWN0aW9uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl

it’s jumped my 12v Cummins no problem

 

[xocyrusx]

Used to have a 2nd deep cycle battery in my old truck to run inverter, winch, and a water pump. I’d like to set up something like that again, one of those rainy day projects on the pile.

It was one of mine... I was at my in laws for 2 weeks so this was a good time to do it.

 

[xocyrusx]

Good idea to be prepared.

I'd like to suggest that you get some good quality military terminals.
They will offer a positive point of termination.
Trust me those wingnuts are not something that you want to rely on permanently.

Second get some covers on your terminals.

When using a dual setup both batteries should be identical.

Thank you. Agree 100% on being prepared. I forgot to mention that was one of the other reasons i wanted to do this. Since in FL hurricanes and loss of power is an issue. With an inverter it’s the best of both worlds. It’s not just a generator sitting there waiting to be used.

I didn’t think about the covers (thank you) which I will for sure have to do. As for the larger heavier connections, I agree the military style connections are best. I’ll have to roll both together for an upgrade.

I went with this specific battery vs the same as my starting as it’s not true inline. This one is designed for true leisure. With the isolator it’s aux power isn’t drawing when the truck is off. From what I researched it’s suppose to be ok but time will tell.

appreciate the response and feedback

 

[xocyrusx]

Years ago a Friend tried this and his alternater couldn't keep both batteries charged. Newer trucks may not have the same problem.

After a couple of days of charging and use I tested it and it was at 80%. I used a battery charger and got it up to 100% but I haven’t tested it afterwards. I don’t want to call it a stress test but I may see about letting it run and drain to see what kind of power and time it can put out alone.

 

[HeavyAssault]

Looks like a great mod. I'd say as long as you used an isolator to feed the second battery you are good to go.

 

[xocyrusx]

Looks like a great mod. I'd say as long as you used an isolator to feed the second battery you are good to go.

Thank you. I am using the 200amp Stinger Isolator. Got it off Amazon for $50...

 

[HeavyAssault]

Nice. I used a Battery Tender on my older truck to keep the batteries topped off. I would plug it in once a month overnight to keep them fresh. Worked great. I'm not sure if that would work thru the isolator. Battery Tender does make a unit that will charge more than one battery at a time.

 

[Powder_Burns]

Also snorkeled the intake and differential breathers. Typical florida man mods. Wish I had pics of everything but that was like 4 phones ago.

 

[HeavyAssault]

I got ya. For my Super Duty we can relocate the diff breathers pretty easily. Just move the hose and clip, done. There are few people who run a snorkel for any reason even with kits to mod out there in the market. I've seen plenty of Aussie Super Duty truck that have them, just not a US thing for us.

With the future of electrical vehicles there will be some pretty cool features for use like you are doing.

 

[308ftWIN]

Just did the same in an 08 Silverado. I used the same type of battery as my starter battery but likely should have gone with a deep cycle for my auxiliary uses. When it comes time to swap out starter batteries I'll probably change it up.

Like you I ran a line off the auxiliary battery to the truck bed. Got it wired to a 6-gang marine panel in a waterproof project box mounted within reach of the tailgate.

 

[xocyrusx]

Just did the same in an 08 Silverado. I used the same type of battery as my starter battery but likely should have gone with a deep cycle for my auxiliary uses. When it comes time to swap out starter batteries I'll probably change it up.

Like you I ran a line off the auxiliary battery to the truck bed. Got it wired to a 6-gang marine panel in a waterproof project box mounted within reach of the tailgate.

Nice!!! Hopefully this yellow top holds up. Could you take a pick of your bed switches? Looking for ideas on the other side.

 

[Ravenworks]

Nice!!! Hopefully this yellow top holds up. Could you take a pick of your bed switches? Looking for ideas on the other side.

Big battery for a little motor.

 

[ajwcotton]

You may want to look into a DC to DC charger. The auto charging system on those trucks isn't ideal for deep cycle or agm batteries.

 

[xocyrusx]

You may want to look into a DC to DC charger. The auto charging system on those trucks isn't ideal for deep cycle or agm batteries.

Any suggestions?

 

[seanh]

Good idea to be prepared.

I'd like to suggest that you get some good quality military terminals.
They will offer a positive point of termination.
Trust me those wingnuts are not something that you want to rely on permanently.

Second get some covers on your terminals.

When using a dual setup both batteries should be identical.

Sounds like you've done this before.

Well I haven't done it on any of my personal vehicles, after working in automotive industry for a little while I was able to see what worked. Terminals are definitely an issue keep them clean and solid. Can't tell you how many times somebody came in wanting a new battery and they just had crappy terminals.

I saw a few customers that replace batteries on a regular basis on their diesel trucks. Why? Number one they didn't replace both batteries at the same time. The other issue was mismatched battery or underperforming batteries.

The people I know that had the best luck added a secondary alternator.

 

[Ravenworks]

Sounds like you've done this before.

Well I haven't done it on any of my personal vehicles, after working in automotive industry for a little while I was able to see what worked. Terminals are definitely an issue keep them clean and solid. Can't tell you how many times somebody came in wanting a new battery and they just had crappy terminals.

I saw a few customers that replace batteries on a regular basis on their diesel trucks. Why? Number one they didn't replace both batteries at the same time. The other issue was mismatched battery or underperforming batteries.

The people I know that had the best luck added a secondary alternator.

Many times

 

[seanh]

Almost forgot, quality cable. Not only do you have to have the proper gauge, but it can't be cheap Chinese. You need a high purity copper, very heavy duty insulation and always go one gauge larger than you need...if in engine bay, 2 if in back of vehicle.

 

[308ftWIN]

Nice!!! Hopefully this yellow top holds up. Could you take a pick of your bed switches? Looking for ideas on the other side.

10ga run from the aux battery under the hood to the truck bed.

The wiring for the marine panel with spade terminals and 12ga wire forced me to go for a little bit bigger box than I would have liked, but still very happy. Used some scrap MDF to fill the extra room in the box to mount the panel to. Top left switch turns everything on,. Bottom switch turns on overhead lights mounted into the camper shell.

 

[Sean the Nailer]

My dad had a '77 F250 Custom Explorer. Had a camper on it, as well as pulled a large trailer (toys) that had a 12v battery in the tongue, just for the trailer winch.

Under the hood, were 3 12v Marine deep cycle batteries. Plus 2 in the camper. Add to that, the one in the trailer, and that's 6 batteries running off the one system.

He'd EASILY be off into the bush for at least 3 weeks at a time. Most often, when it's a fishing trip, he'd be running the electric motor, and hardly ever have to fire-up the 30 horse Honda outboard.

So, those '2' extra batteries under the hood were for the boat. Primary and back-up. The two in the camper were for all the different 12v stuff that he'd run, conveniently. The fridge and furnace and hotwater tank all ran off propane.

He upgraded his alternator to an Ambulance one, iirc it had higher output or something along that nature. Otherwise, that was it, except for 'isolators' and whatnot. I can't remember the details, but, it all worked great.

He'd replace ALL of his batteries at once, and it was generally about every 5 or 6 years. THAT is what got me learning about Pulse-Tech and their offering, to which I get a LOT more life out of my batteries, not to mention stronger/cleaner/reliable'er power.

Don't know if any of this helps or not, just saying that there's much that can be done. It all depends on the OCD degree that you want to pander to. HA. That, and I've got a scar on my elbow and on my forehead, for when I was 12 and I learned not to help your father replace the carburetor gasket on the truck. Or, if you do, take the time to dis-connect the hoses/control wires, to get it out of the way properly.

Instead, he says "stand up here on this wheel, lean over the engine, and hold this 4-barrel carburetor while I clean/scrape off the old one and then put on a new gasket."

It was taking a while, I was over-extended and uncomfortable, and set my elbows down. As the carburetor is bashing into my forehead, and as the top of my head is bashing into to hood above me, I felt like a Pachinko machine there for a few moments.....

You guessed it, I'd set my right elbow down on the positive of one battery, and my left elbow down on the negative of another battery.... and then I got to doing 'the bacon'.....

My dad was PISSED because now he had to re-do all the wires, hoses, and cables to that carburetor because I just destroyed the living shit out of it all.

I still remember that moment, to this day. And it all began with 'extra batteries under the hood'.... Enjoy.