I have a Southern States station locally that sells 50 cetaine. I run it exclusively. On trips where I can only find 40 cetaine I can see a noticeable reduction in both power and mileage. Around town driving I will typically run 280 miles on a tank of 50 and only 260 on a tank of 40.
2007 Silverado Classic 2500HD LBZ, EC,SB, Allison 1000 6 speed, 265's on 16x8" Eagle Alloy wheels, Blocked EGR, PCV Rerouted, BD LH Exhaust Manifold, Diamond Eye Turbo Downpipe, MBRP 4" Front Cat Delete pipe, Banks 4" Monster Exhaust, Banks 3" Intercooler Tube, 50Gal Inbed Auxilary Tank
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