Does anyone know if the isx 15 has egr problems when i drove an international i had those go out all the time. I just had to add 2 gallons of coolant too my pete i cant find any kind of indication where it went. Which leads me to believe its either a turbo issue, the egr cooler or the egr itself. Trucks seems to be lacking pull as well. I was having trouble getting over small hills with 57000 gross. Fuel mileage seems to be going down as well.
May also want to have oil analysis done at next oil change - at least for peace of mind it isn't finding it's way into your oil ... hopefully ..........
