Hi. Thanks for using JA! I will try and help you out.
There are 2 things that I have seen cause antifreeze be pushed out of the radiator over flow.
The first is a failed head gasket. When the head gasket fails, compression from one of the cylinders will put compression into the cooling system. When this happens, you will see antifreeze come out of the over flow.
Second is a failed Jacket Water Pre Cooler. Also known as a JWPC. The JWPC is located after the turbos and before the air to air cooler on the front of the engine. It has antifreeze in it to cool the compressed air that comes out of the turbos. The JWPC can crack, when this happens, boost pressure will go into the JWPC and cause coolant to be pushed out. To confirm, you can remove the JWPC and look for evidence of antifreeze. If the JWPC is cracked, antifreeze will leak back into the piing and JWPC. If you see no evidence of antifreeze, your engine most likely has a failed head gasket.
Please reply back if you need more help or have more questions. I am happy to assist.