Monkeywrench

Remember that driveline torque is limited automatically by weight on drive axle(s). If you don't put much weight on it, the tires just spin, limiting the torque. The other factor is the power which is simply the speed and loads on the driveline. Since the loads are light, so is the power, again limiting the transmission loading. So, no need to rate the transmission to the engine power, rather to the driveline power.