i-love-ramblin

Monaco is using up all their existing ISL07 engines until they run out and then probably use the Navistar engines with EGR in leiu of DEF. All the ISL07 engines are rated at 425 HP and only have the particulate filter system, no DEF . The new ISL9 engines are rated at 450 HP and use DEF. I bought a new 2011 Monaco and was also told adding the DEF was a considerable cost addition and added significantly to the coach's weight. Ed Robbins