251(1)No person shall drive or move and no owner shall cause or permit to be driven or moved on a highway a vehicle or combination of vehicles of a size, with or without a load, or carrying any load, or coupled together, in violation of a special permit issued under section 261 or otherwise in violation of a provision of this Act.

251(2)No local authority has the power or authority to alter any limitation of maximum size or mass of vehicles, except as expressly provided in this Act.

251(3)The provisions of this Act and the regulations governing size, mass and load do not apply to fire apparatus, road machinery or to implements of husbandry incidentally moved upon a highway, or to a vehicle operated under the terms of a special permit issued under section 261.