The more I'm reading the more concern I have...The argument can be made for diesel over conventional gas, but not seeing the 'direct relationship' of the Kubota diesel engine to the HST transmission....with regards to fluid. Some questions were raised regarding the change of fluid to the front axle, as I see it the front axle is an independent component, not in conjunction with the HST transmission...There again those who have changed the axle fluid found metal debris. I'm reading some justification in defense of Kubota...doesn't hold water...In today's day & age with technology metal filings/debris should be a rare occurrence....not a standard accepted condition. My owners manual states change filter @ 50 hrs & fluid @ 400. Convenient,.. by 400 hrs the machine is out of warranty and the damage is already done.... The result of this contamination is Kubota's sloppy quality control in manufacturing, with the debris introduced into the tractor, not as a result of a break in period. I can see this happening in Henry Fords assembly line in 1928 but not today....This uncertainty of fluid change is quite clear now.