M35A3: what is this air-related item part of?

[Sgt Jiggins]

What is the 4-way air junction in the attached picture? It's immediately in front of the steering wheel (in my truck at least) on the engine side of the firewall.

Thanks!

 

[fleetmech]

I'm not familiar with the A3's, but that looks like a later addition, modification or repair, since push lock fittings were not around when these trucks were built. If you follow a few lines, it should give us a good idea.

Could it be for a home brew axle vent or fording kit, distributing air or vent from the axles?

 

[Sgt Jiggins]

I was hoping somebody would have a base system suggestion so that I could go digging through the 1200+ page TM with at least some hope of finding it...

 

[porkysplace]

Where do the lines go to ?
Steering Cylinder ?

 

[Jeepsinker]

Won't be in the manuals. Like he said, this is an aftermarket addition. You'll have to trace the lines yourself.

 

[HDN]

It's on my truck too. The one hose going diagonally down to the driver fender at least goes to the steering air assist system. It looks like another goes to the back of the compressor. Without looking at the TM, i don't know if that's another compressor outlet, but i doubt that it is. One going diagonally up towards the driver fender goes to the air horn. Haven't had a chance to trace the rest.

The A3 trucks use a combination of plastic and metal air fittings.

 

[fleetmech]

It's on my truck too. The one hose going diagonally down to the driver fender at least goes to the steering air assist system. It looks like another goes to the back of the compressor. Without looking at the TM, i don't know if that's another compressor outlet, but i doubt that it is. One going diagonally up towards the driver fender goes to the air horn. Haven't had a chance to trace the rest.

The A3 trucks use a combination of plastic and metal air fittings.

Maybe it was a depot or pre-surplus sort of mod to replace an older/ obsolete/ NLA air manifold with off the shelf truck parts. In ops pic it doesn't look like it or the lines are secured much, maybe they just wanted to get some more trucks moving?
Maybe some A3 guys can chime in if their truck has the same component.

 

[glcaines]

It is not a modification or an add-on. All M35A3s have that four-way connector installed by AM General. It just distributes pneumatic pressure. Also, DOT-approved push-on connectors were used on A3s. It is very easy to see where the air lines go, just follow them.

 

[Sgt Jiggins]

what i'm trying to do is get a replacement for it - it's leaking. the compressor can overcome the leak, but... i'd rather it be right. that's why i was asking- I'm trying to figure out what it's called so that I can get the part from Erik or someone...

 

[HDN]

what i'm trying to do is get a replacement for it - it's leaking. the compressor can overcome the leak, but... i'd rather it be right. that's why i was asking- I'm trying to figure out what it's called so that I can get the part from Erik or someone...

I think I found it here:

Figure 112. Air Compressor and Pipe Cross Air Lines (Front)

Part #9 in the diagram: Part #11669082 CROSS,PIPE

So what I thought went to the steering cylinder actually either goes to the engine fan clutch or the priority valve. I believe the steering cylinder is fed from the priority valve tee, though I can't discern that from the parts TM. The thing one of the hoses goes to on the back of the compressor is the compressor governor, it seems. The other compressor governor fitting goes to the air dryer.

 

[Sgt Jiggins]

That's it! Thank you!!

 

[Potluckslammy]

I have two A3's, and they also have these fittings. One of mine was leaking, as well. Between the local hardware and auto parts store, I was able to replace the majority of these plastic fittings with brass. Only reason all of them weren't replaced is because there wasn't enough on hand to buy locally.
The auto parts store here carries the fittings and the air line for the log trucks, which often have CTIS. Which means...they are available for sale, if not in your area, then online. Mine are Gates branded, with the exception of the T-fitting (pictured), which was a Shark Bite brand PEX fitting.

 

[Lothar]

Having dealt with my fair share of airline leaks, I would recommend using DOT brake fittings to replace any leaking push lock fittings. All push locks seem to leak eventually while the DOT fitting leaks are quite rare. I source them from McMaster Carr. NAPA also carries a good stock.