A computer system has processing circuitry to selectively operate the powertrain system in at least a freewheeling mode, in which an output shaft of the engine is non-rotating, and the engine is disconnected from the one or more drive wheels. The processing circuitry is further configured to: determine an opportunity for the freewheeling mode by predicting a feasibility of restarting the engine along an intended route by using a controllable clutch. Predicting the feasibility of restarting the engine by using the controllable clutch includes determining fulfillment of any one of a first restarting condition and a second restarting condition. Determining fulfillment of the first restarting condition includes comparing current total weight of the vehicle with a threshold value indicative of a minimum total weight for avoiding excessive braking of the vehicle during restarting at a high friction road condition with a given total gear ratio. Determining fulfillment of the second restarting condition includes comparing a current drive axle load with a corresponding threshold value indicative of a minimum drive axle load on a drive axle for avoiding excessive wheel slip during restarting at a low friction road condition with a given total gear ratio. The powertrain system is controlled into the freewheeling mode upon the fulfillment of any one of the first restarting condition and the second restarting condition.
