I drive 95% plus highway and do 60-65 mph and have 37's. my speedo is off ten mph at 60 mph. I use my pmt to know how fast I'm really going because I don't have the speedo gear in my tranny corrected to tell my computer how fast I'm really going. truck says I'm getting 500-525 a tank. my pmt is set to extreme. so I'm really getting more out of a fill up than my truck says
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Bully Dog PMT, 8inch lift, 37" Toyo open country m/t's w/ 22" eagles, 5inch straight pipe, Volant cold air, King Coil Overs, King Shocks, silencer ring MIA , Quadzilla Boost Fooler, Thuren Crossover Steering, Thuren Track Bar