I just put the EZ on yesterday and so far have noticed a BIG difference. The hubby set it at 4, but I don't drive very aggressively. However, it did burn both tires pretty good last night. I love the increased bottom end power that my truck got from it. Don't have to put my foot into it! Good luck.
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2003 Cummins 2500 4x4, long bed, silver, Edge EZ, Silencer Ring MIA, gutted torque tube replaced with AEM dry intake system, cat delete.