garykd Report post Posted August 28, 2009 Earlier this month I had Cummins doing a diagnostic check on the ISC (the reason is another story/thread). I was informed that my ISC required Campaign 0925. There was no choice, it would be installed with or without my permission! . If I declined, any Cummins service center would make the installation, without telling me, the next time I took the coach in for service. Campaign 0925 is an emissions campaign. The stock (straight through) muffler is removed. In it's place is a huge "after treatment" device. The new device is about 3 times the diameter and a little longer than the original muffler. For optimum fuel economy, nothing beats the stock muffler. In layman's terms I feel the new device is as close to a catalytic converter as one can get. The bottom line is I have lost 6/10 of a MPG since the new device was installed. This was travel of 2.2K miles over roads I am very familiar with. Outside of the new device all other environmental conditions were nominal. I guess I can take pride in knowing my ISC now complies with 2005 emissions standards. I will be going on the fall trip in a couple of weeks. Upon completion (November) I'll report back what happened to the MPG. Lastly, the exhaust is much more quiet than with the stock muffler. This is a negative for me. My exhaust is at the left rear of the coach. With the stock muffler, drivers' would pass me very quickly. With the after treatment device, now some tend to sit at the left rear corner of the coach instead of just whizzing on by. For all ISC owners, be careful on taking your coach into a Cummins authorized service center. If I had known about this before they got their hands on the coach, my next visit would have been postponed to way, way, way in the future. Share this post Link to post Share on other sites
mikev Report post Posted October 14, 2009 Hello, I have an Cummings 315 ISC in my 2003 HR Ambassador. Was this mod due to your coach being a 2005 model? Was the cost absorbed by Cummins? Share this post Link to post Share on other sites
garykd Report post Posted November 14, 2009 Hi mikev, I apologize for being so late to answer your question. The campaign is no cost to the coach owner. My assumption is Cummins is paying the authorized service centers a lot of $$$s to ensure they put on as many of these as possible in the shortest amount of time. This campaign is for engines within a specific serial number range. Most of these engines are 04 and 05 coaches. Share this post Link to post Share on other sites
garykd Report post Posted November 14, 2009 I just completed a 4.3K mile fall trip. The loss of about 6/10 MPG remains. The coach averaged 7.8 MPG on this trip. Previous MPG was a consistent 8.4 MPG. The trip was over roads I know very well and all other driving conditions remained as they have in the past. It is unfortunate Cummins is allowed a solution that will cost me $s every time I drive the coach. Share this post Link to post Share on other sites
