What is this thing?

[ten_blade]

Recently bought a heavily modified 2019. Today I noticed a device mounted under the truck, after the rear axle, partially covered by aluminum shield. Only marking is ‘ARB’ and the body of it is blue aluminum, almost looks like an air compressor. Any ideas?

 

[TwizzleStix]

Yep, it’s an ARB onboard air compressor. Likely used to “air up” after an off-road “air down” situation…

 

[ten_blade]

Yep, it’s an ARB onboard air compressor. Likely used to “air up” after an off-road “air down” situation…

Any idea how to use it?

 

[BoostCreep]

Is it maybe wired to one of your aux switches?

 

[ten_blade]

Is it maybe wired to one of your aux switches?

Good point, will try that.

And typically directly connected to the tires?

 

[MurderedOutSVT]

If it's heavily modified, it could be an ARB air locker set up

 

[thatJeepguy]

Front locker.

 

[ten_blade]

If it's heavily modified, it could be an ARB air locker set up

This. Appreciate everyone’s help.

Time to read up on air lockers.

 

[Jakenbake]

You pretty well have it figured out already. It is an ARB air compressor. Looks like a single.

You can use it to air tires up and if you have the manifold you can use it to activate and air locker.

Your truck may have a fabricated diff housing that could use an air locker for sure. Your truck may have a torsen in the front and may not need an air locker up there. The previous owner may have used it to air up tires.

Take a look at the compressor and follow what is going to it and what is leaving it. It needs power, it needs a ground, it needs a signal wire for the relay. Leaving it would be an air hose. Does the hose go to a little tank, the manifold, or a remote air chuck, etc.

There are videos and what not of the arb on YouTube, wiring diagrams on their website, etc.

 

[ten_blade]

You pretty well have it figured out already. It is an ARB air compressor. Looks like a single.

You can use it to air tires up and if you have the manifold you can use it to activate and air locker.

Your truck may have a fabricated diff housing that could use an air locker for sure. Your truck may have a torsen in the front and may not need an air locker up there. The previous owner may have used it to air up tires.

Take a look at the compressor and follow what is going to it and what is leaving it. It needs power, it needs a ground, it needs a signal wire for the relay. Leaving it would be an air hose. Does the hose go to a little tank, the manifold, or a remote air chuck, etc.

There are videos and what not of the arb on YouTube, wiring diagrams on their website, etc.

There is a connection to the rear differential, confirming at least a rear air locker. There is also a relay and a fuse mounted nearby which I didn’t notice before. The relay looks cooked. I tried a couple of the aux switches that aren’t connected to lighting but no action from the compressor.

I guess I’ll replace the relay. I don’t know if there would be another way to turn this on outside of the switches.