Sealed spindles are hard to beat if not abused or pressure washed they last forever. Maybe its the sand and water that make them fail more frequently for some. In 22 yrs of ztr use I have only had 2 failures both greasable either I over greased or under greased them not sure. I have had no failures with 15 sealed spindles so far. So it might be caused by conditions I mow nice green grass, not dry sandy weedy junk like some have too.
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