Complex sentence: The leading pair of driving wheels of the Class NG 15 have a limited amount of sideplay and are linked to the leading pony truck, while the axle of the leading driving wheels still remain parallel to the other three driving axles at all times.
Split into simpler sentences: The leading pair of driving wheels of the NG 15 also have a limited amount of sideplay and are linked to the leading pony truck. The axle of the leading driving wheels remains parallel to the other three driving axles at all times.