I gots to agree with da kyle...unless you run 40's and POUND on your rig, I don't see you breakin a rear axle. Front will go first. Bu then again, its an s10? Spontaneous explosion?
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someone I camped with at the hammers broke a rear shaft with some generic brand 35" tires and he drove his truck real easy. another thing about the chromo shafts it they resist bending by the flange better where the stock ones will bend from jumping or hitting things like mine is.