This might help too got this from a tsb sight for your prob not sure if your dealer checked all this stuff but here ya go
Coolant Expelling From Degas Bottle:
Trucks built with the 6.0 PowerStroke engine may exhibit coolant loss, low coolant, or coolant blowing out of the degas bottle. First, ensure the coolant level is not too high and the expulsion is not due to normal expansion. The coolant level in the bottle at normal operating temperature should be at the MIN mark. 2005 trucks should be checked to see if recall 05B32 applies to them.
The coolant bottle cap should be checked to see if it is capable of holding 16 PSI, and it is sealing properly on the coolant bottle. Pressure test the cooling system to verify there are no leaks. Note: It is advised to either disconnect the right exhaust manifold from the right side turbo Y-pipe, or to raise the rear of the vehicle and remove the EGR valve to check for an EGR cooler leak. Failure to do so may result in a hydralically-locked cylinder. Repair any leaks as necessary.
Inspect the coolant for oil, which would indicate a leaking oil cooler. Check the engine oil sensor reading against the coolant temp sensor. An EOT that is 25 degrees higher may indicate a failed oil cooler. On Econolines, if the engine oil cooler is replaced, the heater core inlet hose should be replaced with part 5C2Z-18472-AA, which includes an internal restrictor. If oil is present in the cooling system, the system will have to be cleaned using a solution of 1/2 cup low-sudsing liquid dishasher detergent to six gallons of water, possibly up to three times. Flush the system afterwards with clean water.
If the coolant expulsion occurs under high load conditions, suspect head gaskets that are leaking compression into the cooling system. It may be necessary to test drive the truck with a pressure gauge TEE'd into a hose and the cooling system sealed so it will not vent to verify over-pressure. When replacing the head gaskets, it is necessary to install new head bolts--they are not reusable. There is a revised torque sequence and specification for the head bolts. The head gasket kits have been revised to include parts needed in the service, but the gaskets themselves are not updated. Recommend using kit 5C3Z-6079-B, which includes all parts for both sides of the engine and covers 2003-2005. You will have to purchase the two intake manifold to head gaskets, oil filter, oil filter base o-ring, oil vent tube o-ring and heater pipe to timing cover o-ring seperately. Note: The turbo should be checked for sticking/overboost to prevent reoccurance of the head gaskets blowing.
TSB 06-3-8.
http://www.intellidog.com/dieselmann/60bulletin.htm