After finishing the install of the Onboard Air, it was only obvious that the next mod should be AIR HORNS.

I did a lot of calling around, and the cheapest price I could find on TRUE air horns was $90.00.

Then one day I passed by a dismantling yard for BIG RIGS, and figured I would give it a try.

After a short tour of the place by Ron, we happened upon a white Kenworth that looked like it had been turned inside out.

I pointed to the roof and asked, "How much?" Ron replied, "$25.00 each!" I said, "get me a wrench!"

These are slightly tarnished, 29" Hadleys, that are in excellent condition.

There are not a lot of places to mount 29" horns in the front, so I opted to install them directly behind the front wheels, one on each side, with a couple of home made brackets.

Let me tell you, at anything over 100 psi, these things ROCK!

The rear brackets are 8" L brackets that have been cut down, re-drilled, and bolted to the side step brackets. The battery box on the right is where the Viar 300c compressor resides.

Since the front mounts had been snapped from the mishap with the truck, I had to fabricate some. I picked up some electrical conduit hangars, and used a 5/16" x 3" machine bolts that not only hold them very tight, but also gives them some adjustment. A wrap of 1/8" rubber sheet protects the horn from the clamp.

Front view of the passenger side horn, with cover in place.

Control for the horns is done with a push button on the dash. The red button operates the horns, and the black button operates another solenoid on the tank that enables me to blow the pressure from the cab if needed. I picked up a Grover valve at the dismantling yard for $25.00. It has a safe working pressure of 130 psi, which is MORE that enough. The solenoid on the tank is made by ARO. It is rated at 150 psi. I picked this one up from Graingers.

All tubing is 1/4" polyprope seamless, and is rated at 150 psi. Fittings are standard hardware store items.