Hi all, I need help on the rear differential and front gear ratios. I have newly installed a pinion gear with 15 sprockets with a 41 sprockets on the big gear. I have changed from 11/41 which had more torque. Obviously, I lost torque now and the max speed of the truck was limited to 60 mph not more. I have a GMC Sierra with a 350 engine and a 400 auto transmission. I need help on the optimal gears to install in my differentials. I hardly go off road and need both speed and torque !