I am posting this for a buddy of mine. He has an 03 6.0. He got a SCT SF tuner about 2 months ago - with the default tunes(not custom tunes). He has had 2-3 different revision to these default tunes due to missing/surging. Are these type of issue normal with the default tunes?? SCT is saying its the truck not the tunes. But before getting the SCT he had a superchips tuner and never had an issue. Any sugestion as to what he can test/try?