Engine blow by

[Lonestar10]

that is water in the oil. you might still see yet more water disapearing as you might have a liner that has broke loose and is leaking water into the oil. diagnose procedure is remove oil pan pressurize coolant system let sit over night after night lay under the truck looking up towards the cylinder bores and have someone bar the engine over and watch to see if water comes out of one of the bores or you hear a gurgling sound like water and air bubbling. if its not there than the check air compressor or anywhereelse water comes near the oil system.