ref GDE, I am also impressed with the up-shift smoothness from 1st-2nd-3rd it is butter smooth. 4,5,6 were never an issue most likely do to additional loading providing a bit of a cushion, and like GMforlife said the hard downshifts are gone. The other thing GDE did for me is they compensated for my 36 Gallon Titan fuel tank. Today when I blew the tune in, I filled my tank and the distance to empty on the DIC is 892 miles... You gotta love that!