I was getting about 5.0 MPG before the EGR cooler and other stuff failed. After $20,000 outlay for new EGR and complete head assembly, I am proud to report that I am now up to 5.5 MPG. The coach is a 2008 Newmar Dutchstar 4304 with a Cummins ISL 425 which weighs about 45,000# and is towing a Ford F150 crew cab. Plan to carry it to Cummins Midsouth in Birmingham after tax season to see if they can help. Given my size and weight, I am prepared to just live with it. I can truly say that I have not owned a 40' coach which has ever gotten better than 7.2 MPG, but the drive and ride has always been worth the price.
