I too do alot freeway driving (11.5 miles one way to work) and one thing you might wanna try is checking the psi about once a week, I mean it doesn't hurt, right. Also, what about running a bit more air as I've heard that helps as well. When it comes down to replacing tires I'm going to see how much I get out of my Pilots and if they last about 20-25K, I'm going with BFG KDW2's as those tires kick as* and have a 300/AA/A rating and look bad as* to boot, for what that's worth.