After force system in diesel engine crankcase and install a transition board between the flywheel shell, the transition plate and the flywheel shell back end joint gear chamber, after the formation of gear after the interior of the gear system will be from the rear of the crankshaft gear output power through an intermediate gear is passed on to the drive gear after force, then through force drive gear and after fixed belt flange shaft power output. The utility model has the advantages of small volume, convenient installation and large output power, which provides convenience for the manufacture and application of a series of special vehicles such as concrete mixer. The utility model adopts a matched oil passage, which can reduce the processing requirements of the oil passage on the premise of ensuring that the lubricating oil has enough pressure and flow, thus effectively reducing the processing cost of the product. The utility model adopts a specially designed crankshaft end gear, which ensures that the same flywheel assembly can be used for the non-rear-force models of the same series of engines