I've got 35k now, mostly crappy on road + maybe a couple thousand miles of off-road gravel. Rotated at about 15k miles, I don't have a tire gauge but was checking the other day and not even close to the wear bars. I keep right around 35psi, even wear all the way around, no problems - I'd guess another 10-15k (which sucks because I want to upgrade to 35s but can't justify it until I need to change tires
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