They get swapped out twice a year at my place. Once during the winter and sometime shortly before all the autumn leaves start hitting the ground in bulk volume.
Very sandy soil & stone in our creek valley and all throughout our property.
I always have them instock, purchased anytime during Amazon sales throughout the year, usually two sets of three at a time/purchase.
Yesterday, they got swapped out and I'm finishing up the first sweep of leaves for the new season.
Also, all grease certs got hit as well. Very important to keep bearings and gears well lubed in these terrain conditions to get the most of these heavily used mechanical parts.
Currently @700 running hours, and still performs perfectly.
Thought I'd share a little more on my 5'/60" 'BIG DOG'.
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