Truck not started, when pedal depressed fluid is spraying inside the MC reservoir. It's looks like its only in the larger section of the reservoir(Rear brakes?). Peddle never gets totally firm. The RWAL hydraulic control valve is a little wet on the bottom side.
What could be causing this?

 

Spongy brakes have air in the system somewhere. Rear reservoir on the M/C is for the front brakes, what you are seeing is normal. Valve might be leaking some..... clean it off good, and hold some pressure on the brakes. See if you can see where it is coming out.

On vehicles that give me grief when bleeding the brakes, what I do, is have my tool slave pump up the brakes three times, and HOLD pressure on the pedal, and then I crack the bleeder valve open. The 'shock flow' breaks loose any air bubbles, and gets a nice firm pedal.

 

It's normal for pressure to be escaping in the reservoir? Seems like if this was the case, you would never get a firm pedal because your pressure would escape. Are you saying this is normal because you believe there is air in the system? Just trying to sort it out in my head. Does anyone know where they sell the RWAL hydraulic control valve?

 

The way the master cylinder works, the primary piston (front brakes), is a bit back from the port that allows fluid into the chamber. When you step on the brakes, the piston has to move past that port before it can start building pressure. It will displace some fluid back into the reservoir before it actually starts doing anything with the brakes. Normal operation, air or not. (try it on damn near ANY vehicle, you will see the same behavior.)

You replace the M/C, didn't you? Did you bench bleed it before installation?

 

Yes I did replace the MC, and I did bench bleed it or I thought I did. Went out and try a friends ram, no spray of oil in the reservoir. I'm going to try and bleed again tonight. First I will do the MC and then the rest of the system. Thanks for the help.
How do I know if the RWAL anti-lock system is working?

 

I am not sure there IS a way to tell. Mine seems to think it is 'working' appropriately..... but, I sure have a hard time discerning a difference. I can still lock the rear wheels, and the computer doesn't seem to care.

I have a rather low opinion of the value of the RWAL in our trucks.