I ran 2 sets of them on my '04 F350 PSD. I found I was getting around 45K kms/set. I switched to Dick Cepek FCII's and am at 42K kms on them right now with about 45% of the tread still left. I run about 70% hwy/30% gravel. For me I won't ever run another set of MT's. Just my opinion.
