Adding a leveling valve

It basically is that easy. You want your leveling rod to be close to horizontal from the valve, and the linkage rod to the axle to be close to vertical. I would mount whatever valve gives you the easiest mounting hole locations. I would also get a popular model of valve, that way if you need to replace it one day, it will be easy to get another one. The Pete guys here can add more details to the actual ride height you are looking for.

 

@NorthernMechanic just had a thread about this

 

While getting one, get one with a dump valve so you can drop suspension if needed

 

What is this used for? I only ask becasue we run car haulers (low-air leaf as well). We run a dual system, normal right height is where they stay most of the time, but with the low trailers, they have a switch on the dash to lift the drives and trailer about 4" to help get over railroad tracks and stuff without scraping the rails. Our system is just 2 leveling valves, 1 set normal, the other set to near maximum on the bags. We use a pilot valve to switch between the two operated by an air switch. Since high lift throws off the drive line angles, they cannot drive fast, so on high lift we have a warning buzzer. They only use it to creep over a hump in low gears.

I only mention this because if your application has a use for adjusting the pressure manually, you could keep it and use a pilot valve to switch from the leveling valve to your pressure valve. If you don't need it all, simplify everything and just use a normal leveling valve.