?? white smoke at idle but not on highway, EGR or headgasket??

[v-DOGG]

2007 e 450 6.0, i have white smoke during start up and idle but not driving on highway speeds, antifreeze is coming out my taillpipe and degas tank pressure spikes high during at engine load. want to know whats the best way to determine if the headgaskets are bad along with the egr cooler. it has about 75,000 miles and i know for sure it is going to need the egr and oil cooler. I would really hate to just change the egr cooler and later find out the head gaskets are bad..... your advice would be appriciated!!!

[southend]

The only thing you might do is pull the egr ands see if there is coolant in the intake.

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