The system synchronizes speed of drive wheels. Speed of wheels which is skidding is automaticallylimited to speed of the second wheel with which it is synchronized.• Wheels paired for sychronization are always placed on opposite side of the rail in order to limitskidding caused by eg. oil spill on the rail.• Main pump system always keep high pressure in order to provide constant full pulling capacity.• Wheel which is skidding do not damage.• System may be deactivated from operator’s cabin.