which by-pass? FS-2500, Amsoil or other? Much on there is still foreign to me but when I can get essentially double mileage out of the oil I'll take it?

Patrick

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2008 2WD 2500 QC Short Bed, 3.73, G56, PML Rear Diff Cover. Wheel to wheel 3" Nerf bars, AMSOIL Dual By-Pass AMSOIL In Crankcase, Tranny, and Differential