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My 2004 express 3500 has been puzzling me for a while. All things constant,70 psi new tires, straight rims, paved road driving etc my passenger rears wear out only on the inside. Wednesday the inside blew out at 65 and I limped home 30mph. Can leaf spring perches or u bolts cause this.? Driver side wears flat and evenly. I have 290,000 on it and I maintain it as needed. New control arms, full brakes (drilled and slotted) new axle seals and diff fluid. I've owned it about 7 years and it's always worn them like this. Suggestions? I'm new here so hello.!