I'm working on a '09 Maxxforce DT that the DPF is constantly getting facepluged with soot. The engine runs fine with no smoke and passes both the standard and air management tests. There is some soot blockage of the EGR coolers as well as some oil film in the turbo hoses but nothing alarming and no excessive play in the turbo. When performing an after treatment cleanliness test the EGT's only get to 450deg. According to the manual they should reach at least 750 deg. but my local dealer who just did a reflash is telling me that 450 deg. is correct. Any thoughts on the faceplugging and 450 deg. EGT's during a cleanliness test? Thanks in Advance!