(5) Operations authorized to exceed the limit on the number of vehicles that may be operated in combination by a variance permit issued under ORS 818.200 are subject to the terms of the permit. It shall be a defense to any charge of violation of ORS 818.110 if the person so charged produces a variance permit issued under ORS 818.200 authorizing the operation of the combination of vehicles issued prior to and valid at the time of the offense.
(6) In drive-away operations, three vehicles may be coupled together by a double saddle-mount method or by a single saddle-mount and tow bar method or four vehicles by a triple saddle-mount method.
(7) A combination of three implements of husbandry or two implements of husbandry hauled or towed by another vehicle may be operated on a highway without violation of the limits under ORS 818.110.
(8) A truck tractor and semitrailer drawing one trailer or a truck tractor and semitrailer drawing one additional semitrailer mounted on a dolly equipped with a fifth wheel hitch may be operated on a highway without violation of the limits under ORS 818.110.
(9) A truck tractor and semitrailer drawing a balance trailer with a length not in excess of 15 feet and a loaded weight not in excess of 8,000 pounds or drawing a dolly may be operated on a highway without violation of the limits under ORS 818.110.