Slipper Upgrade Torque Control Slipper X-MaxxT Maxx Torque Control Slipper Upgrade Kit (fits first generation T Maxx transmission, w o Optidrive) The Revo Spec Torque Control slipper clutch upgrade kit fits T Maxx Classic, S Maxx, and SportMaxx trucks equipped with the original T Maxx style black transmission. It features efficient semi metallic friction pads and allows for spur gear replacement without altering the slipper clutch setting. Kit includes everything needed for the conversion, along