I have an 2005 cummins with 44,000 Miles on it. I installed a MBRP 5" exaust (with muffler), K&N ram air, and bully dog triple dog with outlook. Shes been running fine until a couple weeks ago when I went out to start her and she was running very rough. She seems to run fine after warm up and running highway speeds, but when I start running stop and go traffic she starts to run rough and it feels like the truck is shaking. I noticed that the exhaust smells a little "rich". I changed the fuel filter and that didn't change anything. I got a little worried so I made an appointment at Dodge to get it fixed... any ideas on what is causing this problem? Is it major? Will dodge still honor the warranty or am I S. O. L due to the mods?