The primary function of commercial vehicles is to support the efficient and timely delivery of goods, contributing significantly to the nation's economy. Straight trucks and tractor trailers are two prominent types of commercial vehicles that serve distinct purposes within the transportation sector.

The WD615 series diesel engine is a world-advanced engine introduced by Weichai from Daimler-Puch in Steyr, Austria. The total displacement of this series of diesel engine is 9.726L, there are naturally aspirated, supercharged, supercharged and intercooled models, the basic speed of 2200-2600R /min, Power range 176kw-280kW.