Just a video of my 2500hd with the 8.1 liter allison 5 speed transmission. pcm4less custom tune k@n cold air intake, magnaflow true dual exhaust, chipped. dyno 485 which is pulling power for this truck. this truck is not set up to race but i have ran a duramax diesal and ate him for dinner lol. the whining you hear is not the motor about to blow up its a tensioner pulley going bad.