The lowered position is for {HEAD ~ long distance haulage} of {TAIL ~ the trailer} in order to achieve fuel economy 
of
The lowered position is for { HEAD ~ long distance haulage } of { TAIL ~ the trailer } in order to achieve fuel economy
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH