Dodge Ram 1500 4.7L, 2003. The engine is constantly overheating, due to pressure getting into the system. Changed the fan clutch, (It was broken), and solved the cooling problem, but there is still pressure in the water system, and, due to using 98% antifreeze, can't be from evaporation; leaving something -else- to cause pressure. No water in the oil, or vice versa, no burning oil, or even excessive bubbles in the water system; and yet, the water is still being forced out from the overflow. Radiator cap is new, too, and no visible damage on the gasket. Any ideas?
Check your radiator. I recently had the same issue. I change the thermostat, fan clutch, temp sensor and water pump and my truck still ran hot. Pull drain plug and see if there is a trash build up in radiator.