... tractor truck is used for all kinds fo semi trailers, for example,It's used for the cargo ... semil trailer, the lpg semi trailer,the flat bed semi trailer,etc. We can design and produce this tractor ... trailer is towing the rear of the tractor.The tractor only provide the forward pulling force. ... ,fire engine,spares,refrigerator truck,water wagon,tractor,high-altitude water truck,bulk cement truck ...