I recently went on a trip pulling a 28' travel trailer with my 07.5 dmax aem brute force intake-bully dog power pup. fault code 2459 three times then into limp mode went to dealer they performed a service dpf regen then sent me on my way. Meanwhile on my way back running stock program the 2459 came back two more times. I have not ran anything but ULSD fuel. Just recently went to dealer and got the ECM update for the 2459 code. I don't understand why this code kept appearing since it means (regeneration frequency too high) that the dpf would become clogged if it is regenerating?:rolleyes:

Welcome to the land of emissions. You can do nothing but drive and wait for the next time your trucks brain decides to have a brain fart. GM has so many updates for these trucks its insane. I was talking to the service manager of a dealer yesterday and he told me updates for these trucks come in on a daily bases. GM can't even figure it out. You come in we clear the code flash you with the latest and the greatest down lodes, and send you on your merry way. And if you keep coming back we will just give you another up date and have you test drive that program for us. I've had my truck back so many times, when I go in, they look at me like what should we do now? Oh just give it another brain transfusion and I'll see if I can't kill myself the next time it decides to limp on me."OK thanks and good luck this time"

jdreck, I had the same problem and if you do a search there is another thread I started about this code. I had it once, but never again. I now have no DPF so no more of that code! Good luck.

Glad I read this... Keeping my original programming... Don't need to go thru update after update, ala Ford 6.0.