A mobile fracking pump trailer 100 includes a gas turbine engine 102 and fracking pump 104, and torque converter 114 that fluidly couples the gas turbine engine 102 to the fracking pump 104. The mobile fracking pump trailer 100 further includes a first reduction gearing 118 connected between the gas turbine engine 102 and the torque converter 114 and a first power takeoff 120 connected to first reduction gearing 118. An electrical machine 128 is connected to the first power takeoff 120 for selectively starting the gas turbine engine 102 and generating electrical power to power the mobile fracking pump trailer 100 after the gas turbine engine 102 has been started.