Went to the ford dealership today to have my oil and filters changed, amsoil oem heavy duty diesel 10w40 I believe whatever factory calls for. Fomoco oil and fuel filters. Changed them get home and pulled into the garage and noticed a loud tapping/ knocking sound around 850 to 1700 rpms. Can't really hear it over the turbo above that. Also smell diesel fuel pretty strong which is strange considering with these fancy particulate filters I have never smelled it truck has roughly 51k miles. Called the dealership and am taking the truck in at 8 am tomorrow but the diesel tech hasn't impressed me thus far obviously. Wanted to get armed with some knowledge before I go back in there. Any help would be greatly appreciated thanks guys.