My custom Onboard Air install

[FirstAscent]

Hey everyone,

 

I wanted to share my version of a custom onboard air compressor install with full custom wiring harnesses too!. There's of course many ways to do this so maybe this will help some of you if you're considering something similar.

 

I first want to specifically thank @Limelight and @mkeddie as I've taken some of my ideas from them. I used a similar mounting location as @Limelight, and @mkeddie had a great upfitter post that gave me the perfect solution for running an air line from inside the cab to the bed of the truck in a clean fashion. So, thank you guys!

 

I've always wanted onboard air for various reasons, but now I "needed" a solution because I just installed airbags for the first time but I didn't want a compressor that was only dedicated to the air bags, I wanted to be able to use it for whatever I want whether filling up truck tires, or mountain bike tires, or float tubes, or whatever!

 

I opted for the ARB Twin Compressor (Part # CKMTA12) because it will give me good output and let's be honest, it looks pretty cool too! I spent quite a bit of time determining the best location, for me, to mount it. I considered just about everywhere including under the body/bed, in the engine bay, in the truck bed and finally settled on mounting it in the larger factory GM rear underseat storage. 

 

Now to decide on the wiring and general function/control that I want since it will all play together differently depending on how I wire things. I also wanted room for change and/or additions in the future so I knew I wanted a fuse box. 

 

I knew I wanted the to use a solenoid that would enable the new fuse box entirely with Accessory (ACC) power instead of having individual relays for anything connected to the fuse box. Going this route also means I need a solenoid that can handle larger loads. I found a Stinger SGP32 200amp solenoid, and the just about PERFECT place to mount it. 

 

These two bolts are almost perfectly spaced to mount the solenoid, this in is in the engine bay kind of on the inside of the front passenger fender.

 

 

The tabs on the Stinger solenoid were already cut out for mounting bolts in them but I had to slightly cut them out a little deeper so that the spacing would fit the existing bolts shown above.

 

The factory body panel bolts have permanent washers, but there was just enough play in them to slide the mounting tabs in between the bolt head and washer, PERFECT. You can see the body panel is somewhat indented at the mounting point as well, to fill that space to the bolt can be tightened down properly I just added a couple washers beneath it. 

 

Here it is wired up, 4 wires total.

1 wire to the ground lug you can see in this photo

The smaller black wrapped wire is my ACC power wire to enable it that runs across the engine bay to the driver side and through a rubber nipple in the firewall to the BCM

The large red power wire is fused to the secondary battery (I have dual batteries)

Then there is one more wire that runs through the firewall and back to the rear seat where my fuse box is.

btw: I hand wrapped these wires with tape for wire harnesses, took forever! haha

 

This larger black wire connected to the MEGA 125A fuse (with green text) is coming from the solenoid. This spot is meant for the factory snow plow power, but I won't ever have a snow plow, so perfect use of good space!

 

This is me prepping the power wire before connecting it to the solenoid

 

This is the other end of the positive wire from the solenoid that went through the firewall, along the door sills, and then I cut a little bit out for the wire to come out of the rear passenger door seal to under the rear seat.

 

Clean routing of the power wire from the solenoid to the battery

 

Here you can see it start to come together. The purple wire is the power wire from the solenoid to my fuse box

Remember this entire fuse box will be enabled by ACC power. 

On the top right of the fuse box you can see the main ground wire, it is grounded to the body near the factory jack.

The black box on the left mounted vertically is an ARB Linx, I'm using this for control of my compressor, air bags, and future I/O expansion.

 

This is that ground wire, I had to slightly drill out the whole that was already existing to fit the 1/0 AWG wire

 

Here is how I'm going to connect it to the factory threaded stud that secures the jack

 

I got the Dremel out to take the black paint off the surface of where the ground point would be.

 

 

 

 

[FirstAscent]

The compressor can be controlled wirelessly from a dedicated display on the ARB Linx the I have mounted near the steering wheel. But just in case anything were to happen, I can also manually activate the compressor with a hard switch

 

The door closes with just enough room to spare!

 

This is my air solenoids that control my air bags. Again, this is wirelessly controlled from the dedicated display to any PSI I want

 

Backseat removed prepping for running two air lines from the compressor to the exterior

1 air line the splits into two for the rear air bags

1 air line that will run to the rear foot step in the rear bumper for standard compressor use with a quick connect female fitting

 

I didn't get a photo of it but there are now two air lines running through the floor just like this one. 

 

The air line from the solenoid goes to my airbags

The airline with the blue/red fitting goes to the rear bumper

BTW, this fusebox is the SafetyHub 150, it supports both ATC and Midi fuses! I needed both and this does it all, it's super solid and well built too!

 

This is a female quick connect fitting for connecting any male quick connect fittings to for filling up tires, toys, whatever. 

 

This is what the dedicated display from the ARB Linx looks like.

Notice all the ARB wiring in the background, I got rid of all of this and made my own harness that only included what I needed and the exact lengths!

 

From this screen I can turn the compressor on or set my PSI for my air bags and create different settings as well (unloaded, towing trailers, hauling various loads etc)

 

If anyone has any questions, let me know. I had a lot of fun with this project!

 

Edited June 13, 2020 by FirstAscent

[Black02Silverado]

Great write-up!  Thanks.

[kgr]

I'm looking to do exactly this. Maybe a small tank as well?

[FirstAscent]

I'm looking to do exactly this. Maybe a small tank as well?

For me I don’t need a tank. I’d only consider one if I was running pneumatic tools where I needed to maintain a specific pressure.

So far I’ve only used the compressor for some basic tasks:
Adding air to tires
Inflatable SUP’s
I also have it tied into my airbags so it gets used daily to adjust them on the fly

It’s handled everything like a champ

[kgr]

On 6/12/2020 at 10:46 PM, FirstAscent said:

The air line from the solenoid goes to my airbags

The airline with the blue/red fitting goes to the rear bumper

 

Right ok, well maybe that's enough for me. I don't *plan* to use air tools.

 

So did you just add the additional T to split supply to air bags / aux use?

 

And did the compressor come with that solenoid & wireless controller or was that another kit?     *EDIT* sorry I think I get it - its the ARB Linx that provides the wireless interface?

 

Maybe you could shoot me some details on the stuff you used? I have an amazon seller recommending this air bag kit: https://www.amazon.ca/dp/B07Z43GH3Y?  but I'm undecided on a compressor as of yet.

Edited September 9, 2020 by kgr
can't read lol

[FirstAscent]

Right ok, well maybe that's enough for me. I don't *plan* to use air tools.

 

So did you just add the additional T to split supply to air bags / aux use?

 

And did the compressor come with that solenoid & wireless controller or was that another kit?     *EDIT* sorry I think I get it - its the ARB Linx that provides the wireless interface?

 

Maybe you could shoot me some details on the stuff you used? I have an amazon seller recommending this air bag kit: https://www.amazon.ca/dp/B07Z43GH3Y?  but I'm undecided on a compressor as of yet.

 

I have two Tee’s in my setup, I Tee off the compressor itself- one line goes to my non regulated quick connect fitting (think standard air line for filling tires etc) and the other line goes to my air bags. The line that goes to my airbags also has a Tee, and one line goes to the left air bag and the other the right air bag.

 

I don’t need it want individual control of my left and right side air bags, setting them at the same psi works great for my needs, and most everyone else too.

 

The ARB Linx is the wireless setup and is kick a$$, I love it. It’s pretty spendy but I love the functionality, control, and expansion capabilities. It’s a separate purchase, I also had to purchase the airbag solenoid separately, the Linx system is very modular. The base Linx setup is the wireless controller and an Input/Output module (main hub) where all the wires go back to.

 

My airbags are the Airlift Loadlifter 5000 Ultimate Plus, I like what the company is doing with their product and their internal jounce bumper. Although with my setup, I could’ve installed anything, the air compressor doesn’t care what it’s filling up haha. If I were to do it all over again, I’d do it the exact same way.

 

I actually have this quick sketch I drew up on my iPad when I was drafting my air lines so I didn’t forget any karts to order. This kinda gives you a visual on how I routed my lines and where my Tee’s are.

 

I hope this helps, and happy to answer any other questions!

 

 

[kgr]

17 hours ago, FirstAscent said:

 

I have two Tee’s in my setup, I Tee off the compressor itself- one line goes to my non regulated quick connect fitting (think standard air line for filling tires etc) and the other line goes to my air bags. The line that goes to my airbags also has a Tee, and one line goes to the left air bag and the other the right air bag.

 

I don’t need it want individual control of my left and right side air bags, setting them at the same psi works great for my needs, and most everyone else too.

 

The ARB Linx is the wireless setup and is kick a$$, I love it. It’s pretty spendy but I love the functionality, control, and expansion capabilities. It’s a separate purchase, I also had to purchase the airbag solenoid separately, the Linx system is very modular. The base Linx setup is the wireless controller and an Input/Output module (main hub) where all the wires go back to.

 

My airbags are the Airlift Loadlifter 5000 Ultimate Plus, I like what the company is doing with their product and their internal jounce bumper. Although with my setup, I could’ve installed anything, the air compressor doesn’t care what it’s filling up haha. If I were to do it all over again, I’d do it the exact same way.

 

I actually have this quick sketch I drew up on my iPad when I was drafting my air lines so I didn’t forget any karts to order. This kinda gives you a visual on how I routed my lines and where my Tee’s are.

 

I hope this helps, and happy to answer any other questions!

 

Wow that's awesome, thanks man. I think I'll set up my system like that, except Linx... I checked it out and it looks really killer - but I'm not in a position to go that far yet. Maybe later lol.

 

I do tend to agree with your comment about the Loadlifter jounce bumper. I'd be interested in any comments you have about the use / durability of the product itself.

[FirstAscent]

Wow that's awesome, thanks man. I think I'll set up my system like that, except Linx... I checked it out and it looks really killer - but I'm not in a position to go that far yet. Maybe later lol.
 
I do tend to agree with your comment about the Loadlifter jounce bumper. I'd be interested in any comments you have about the use / durability of the product itself.

For sure! And yeah the Linx is nice but most definitely not required!

Well take my loadlifter opinion with a grain of salt in that I don’t have a lot to compare it to. The idea behind it is sound, and I’ve never had airbags before but the before and after feel with anywhere from 0-5psi felt good, similar to no airbags. I like the piece of mind of having the bounce bumper though.

I haul a 16k lbs 42’ fifth wheel toy hauler so that’s my reason for wanting air bags. Depending on the load and weight of the trailer I like being able to dial in rear ride height for extra support.

Too soon for durability but so far I’ve had zero issues and it does what it’s supposed to do.
Build quality is excellent and all parts felt solid.

[ekbruster]

Nice setup, just ordered the ARB for my 2500HD AT4, was curious if you had any issues with heat-build-up on the compressor being under the seat?  Want to mount my in the same manner (minus the Linx) funny enough was looking for doing the same with putting the quick connect in the foot wells.   

 

Was there a grommet you tapped out for the airline leaving the cab or did you just drill the holes directly?

 

Awesome work

[FirstAscent]

Nice setup, just ordered the ARB for my 2500HD AT4, was curious if you had any issues with heat-build-up on the compressor being under the seat?  Want to mount my in the same manner (minus the Linx) funny enough was looking for doing the same with putting the quick connect in the foot wells.   
 
Was there a grommet you tapped out for the airline leaving the cab or did you just drill the holes directly?
 
Awesome work

Hey thanks man, I appreciate it. It’s honestly been perfect, not a single issue and I’m happy with the locations of everything as well.

I was kinda thinking the same as you at first with the heat build up but I’m not concerned at all now. First co soldering it’s only running when air is needing to be supplied which probably isn’t for hours on end.

The longest use of constant supply I use it for is filling up an inflatable paddleboard which is just over 5 min straight and it doesn’t get anywhere near too warm where I’d be concerned. Other than that, filling up tires or adjusting the air bags is barely long enough to build up any heat.

I also really like having the quick disconnect in that footwell near the bed, if I were to do it all over again I’d put it in the exact same spot. It’s so convenient.

There was no grommet where I drilled to exit the cab, I drilled a new hole large enough for the air line and put one of those cable glands there to keep water out.

Let me know if you have any other questions!

[ekbruster]

Finished all my wiring, still have to run my airlines...  Surprised on how quiet it is back there, thought it would be a LOT louder.

 

[FirstAscent]

Finished all my wiring, still have to run my airlines...  Surprised on how quiet it is back there, thought it would be a LOT louder.
 

Heck yeah man nice work! Yeah the noise isn’t bad at all. I take my dog everywhere with me and she doesn’t even mind it when she’s sitting on the back seat and the compressor kicks on.

[clubba]

This is a great writeup! I'm wanting to install on-board air and thinking of going with the single compressor (ARB CKMA12) mounted in the second battery bay under the hood (I only have a single battery setup). I will use it almost exclusively for filling tires on the truck and travel trailer, and occasionally a SUP or inflatable raft. It would only ever be used with the truck running or in ACC and with the hood open. It would never run with the hood closed. Any issues with that location - being exposed to engine bay temperatures for prolonged drives when not in use - or any other reason? 

Edited April 23, 2021 by clubba

[Brozat4]

Glad is stumbled onto this thread, I have been running this idea through my head as well. Quick question though.

 

How is the ride when empty and what PSI do you run them empty? The reason I ask is because prior to owning my 2020 3500 I had a 2016 1500 with air bags and even empty the ride was quite rough... I'd even venture to say it was stiffer than my 3500 is stock.