empire paving

I have a 2007 ctp 713 dump truck that will use 2 gallons of coolant a day, there is no sings of leaks, I have not had it pressure tested, but have checked the lines for cuts, bulges, ect. Not going into oil. I brought a piece of equipment to a local cat dealer and he said they had issues like that with their egr valves. Does mack use egrs? I called my mack dealer but conveniently they didn't get back to me because I was looking of info, not making an appointment. Any suggestions will be appreciated. Thanks.