Have had my Viperspec T56 for about 8-9 months now and want to swap out my differential gears to ones that work well with the Vspec gear ratios. I have been running 3.55 and its very highway friendly. What gears are ya'll running?
My buddy is doing the T56 swap right now....funny thing though, you gotta pay attention to the gear ratios that your T56 has. I'm not sure how the Viper spec version differs, but he found that 6th in his T56 has the exact same (well, extremely close to) the same gear ratio as 5th in his T5...meaning that it isn't going to make a bit of difference on the highway. Then we got to looking into the other gears and they're all very close to a T5 with basically an extra gear between 4th and 5th to make 6 speeds. He's running 3.73s and it purrs on the highway.