I spent a lot of time analyzing the problem and being that I have both the homeowner version snowblower and the commercial version of the snowblower the issue doesn't change one bit. It is the lifting of the snowblower that is the culprit. Last winter I was experimenting with wooden blocks to limit the amount of lift that the blower would have, but never found an easy solution of keeping the wooden block in place. I just resigned myself to only lifting the blower the bare minimum to prevent the wear of the cogs. There is a local business that does heat-treating hardening of steel, so if I have to replace mine, I will have the replacement parts hardened first. I just hope that they will do a single part for me. I feel relatively confident that the steel that RAD Technologies Inc. (manufacturer of the Kubota snowblowers) is a mild steel that can't hold up to the abuse that the K Connect puts on it. I have no idea if Kubota Corporate is even aware of the problem because many times it never goes beyond the local district manager when a problem such as this occurs.
I believe that if we all were to complain to the manufacturer it would get their attention and their engineering staff will need to address the failures. The manufacturer has an excellent reputation in the manufacturing sector for providing quality snow removal equipment. The most important thing that all of us can do is to photo document the failures and whenever possible get the defective parts back into your hands for analysis by the manufacturer.
One final thought, there is a small 1/4" diameter bolt that holds the cog to the snowblower. It is a grade 5 bolt as best as I can tell, since the service replacement has no head markings. I have purchased this bolt from 3 different Kubota dealers, and not once did it come in a Kubota package. This leads me to believe that the dealer's parts department is buying this part in volume and not from the snowblower manufacturer. My snowblower has broken this bolt multiple times, and while the part has never fallen off, it does allow the part to move both for and aft. I was advised not to replace this with a harder bolt in the past and I have headed that advice. I am wondering if a stronger bolt might be a better choice. If you have experienced this bolt failure, please tell us how often and what you have done about replacement bolts. Only our shared knowledge of failure and success will resolve this problem for all concerned. If we keep posting our individual experiences in the same thread, it will help everyone to know that they are not alone,