How Should OEMs Balance Start-Up Torque and High-Speed Efficiency When Selecting a Multi-Speed E-Axle?
A heavy truck that leaves a depot at full load asks something very different from its drivetrain than the same truck cruising at highway speed an hour later. At launch, wheel torque matters. On a long, steady section of road, keeping the motor in a more suitable operating range becomes increasingly important. Trying to cover both ends of that duty cycle with one fixed reduction ratio can force compromises elsewhere in the drivetrain. A multi-speed e-axle gives engineers another option, but it also introduces more hardware, calibration work, and shift-control requirements. The useful question is therefore not whether two speeds are better than one. It is whether the vehicle […]