coolant loss

[flonly]

Ok 2008 cm 871 demandated at mr haggs and inframed at same time.My truck is a t660 so it has the transmission cooler in the bottom of transmission that has coolant lines going into it.I was running last night and low coolant dummy light came on.I got off road and sure enough coolant low.I could not find a leak externally but shut off heater vaves to isolate that but i ran about 60 miles to get my run done and seemed like i lost more coolant.Now I know there was a blocking plug used when mr hagg did demandate but that was for the exhaust gas part so if its the cooler then where should I look to see if its the cooler.If i am loosing that much coolant due to the cooler and its getting in the oil shouldnt i see extra fluid on oil dip stick?.I am going in around 2 pm and I can check the transmission fluid cause i think coolant makes it milky colour but need to know where to look in the egr cooler side of missing coolant and i can pull a oil sample but not sure how long to get results back.thanks