PJ, My dealer informed me while I was in for service on my 2005 Super Z that there could be a problem with my mowers gear box. He gave me the name of the area rep, I called him and he confirmed that Hustler would like to replace my 26 hp LC engine with the 25 hp Kawasaki air cooled engine due to some problem with the gear box. I purchased my Z last summer and I only have 60 hrs on the machine. This is an optional recall. Would you please explain to me the actual problem in more detail and why this subject has not been mentioned on this forum previously. I am a bit puzzled about all of this.