Hi everybody. I have used this site numerous times to troubleshoot some issues I had been having with my 2010 6.4. Recently I got the P040D code and couldn't find a clear answer or solution to it. Just bits and pieces here and there but no part #s or how to guides on a fix. So today I joined so I could lend anyone else out there in power stroke land a better explanation of the issue and the cure with part numbers TSBs the whole nine. Hope it helps!!!