A powertrain system for a machine is described. The powertrain system includes a power source configured to provide a torque output. The powertrain system further includes a first drivetrain coupled to the power source, to drive a first set of ground engaging members, and a second drivetrain coupled to the power source to drive the second set of ground engaging members. The powertrain system further includes a controller having one or more lug curve maps defining a maximum allowed torque value of the power source for a current operating condition of the machine. The controller is configured to determine a parasitic load due to the second drivetrain, and adjust the torque output of the power source based on the determined parasitic load to maintain a rimpull performance of the machine, where the adjusted torque output is limited by the maximum allowed torque value.