Is Shimano quality what it used to be? I have XT hubs on my MTB training hack and they are over 18 years old. The seals are excellent, the grease is always spotless when stripping down and re-packing. The hubs have done more miles than I can remember and I have just built the rear one into a new rim (which had worn through) for many more years of abuse use.
I clean this bike once a year whether it needs it or not! It lives happily under a thick layer of grease and waxoyl
Interesting question. I suspect it might well prove not to be the case. Perhaps they realised their original XT components were too well engineered so in effect down graded them to fail sooner ie after a short period outside the warranty.
Anyway Shimano is crap compared to Campagnolo

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In the 1960's, 70s and 80s Volvo and Saab made cars with a view to them lasting 20-30 years. Not now. Most vehicle manufacturers want their cars to fail sooner, obviously not 2 months after a 3 year warranty has run out as no one would buy them, but say after 8-10 years so consumers have to purchase another.
I think Shimano may have adopted the same strategy as I seem to remember another thread maybe on CC or elsewhere suggesting the new XT range was of reduced quality whether the grade of materials, hub flanges or free hub or seals I cannot remember but it wouldn't surprise me. I have a a 2 year old XT rear hub on one of my bikes but I don't ride it enough to say whether it has lasted well or not.