Hello eXmark, I just purchased a new 36" TTHP & it came with the old Kaw & not the K-series w/the better air filter. The eXmark rep was there when I picked it up & was very apologetic & offered an eXtra year on the engine warranty. He also told me that it was an 04 unit. Is this true that you are shipping o4's w/out the k series Kaws... I was a bit disapointed that I ended up w/the old Kaw after thinking I was ordering the 04 TTHP w/the new Kaw. Unfortunately the 15Kaw had been removed by my dealer, placed on my Viking 32" & a K-series 17 Kaw had been fitted to the 36" TTHP, so returning the mower would have entailed swapping back the engines. If you can still follow this I wanted the K-series that should have been on my 04 TTHP on the Viking & not the old model Kaw that came w/the TTHP. I'm just wondering if this mower is in fact an 04 as it had the old Kaw..serial #414528. & no worries the rep & my dealer did everything to try to make it right & I'm satisfied w/ the eXtra year on warranty & a few filters thrown in to compensate. Heres the Kaw that came w/ my 04 TTHP...its now on my Viking 32".