Two 94-tonne electrical transformers bound for a green energy project arrive by ferry from Rotterdam. Veteran heavy haulier Gavin and his protégé Rob must transport them from Immingham Dock in Lincolnshire to Aberdeen. The three-day, 450-mile journey will be on 116 wheels, attached to two 630BHP Mercedes trucks and two 27-metrelong trailers. Including support vehicles, this convoy is as long as a football field, and tomorrow they must meet their Police Scotland escort. But getting north of the border today will prove an almost impossible challenge. After an hour on the M180, there's smoke billowing from Gav's trailer. An impromptu hard shoulder stop has Rob getting down and dirty to clean a brake airline. In west Yorkshire, with M62 traffic rushing past, there's another smoking brake that can't be fixed by Rob, so a mechanic is called to pry the brake shoe free. Now the race is on to escape the county's rush hour heavy haulage vehicle embargo. At an average speed of just 30mph, making