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(1) A "special vehicle combination" is a truck-trailer-trailer combination of vehicles or truck tractor-semitrailer-trailer-trailer combination of vehicles as defined in statute and in 23 CFR 658, appendix C, April 1, 2015 edition. Copies of the regulations may be obtained from the U.S. Government Printing Office, 732 North Capitol Street, NW, Washington, DC 20401-00012, or at www.gpo.gov.

(2) No special vehicle combination may be operated without a valid overlength permit.

(3) Special overlength permits shall be issued to a specific truck or truck tractor and are nontransferrable, and may not be used for any other combination other than a "special vehicle combination" as defined in this rule.

(4) In addition to the special overlength permit, the operator must obtain all other necessary permits for travel in Montana.

(5) When a terminal is beyond a two-mile radius of an interchange on the interstate system, the Department of Transportation may authorize travel between the terminal and the interchange. The operator shall apply in writing to the Department of Transportation for authorization to travel outside the two-mile radius to reach a terminal. The written application must specify requested routing and show good cause why the travel is necessary.

(6) The Department of Transportation may restrict or prohibit travel of special vehicle combinations to specific routes, hours of operation, specific days, or seasonal periods, when adverse conditions, traffic, weather or other safety considerations make such operation unsafe or inadvisable. Special vehicle combinations shall not be dispatched during adverse weather conditions, as defined in section 392.14 of the Federal Motor Carrier Safety Regulations. If adverse weather or road conditions are encountered or if the road surface is icy or snowpacked, the driver of the special vehicle combination shall proceed to the next available exit or turnout and drop a trailer or wait for conditions to improve. If road or weather conditions are deemed sufficiently hazardous by the Montana Department of Transportation or the Montana Highway Patrol, they may instruct the special vehicle combinations to cease operations immediately until such hazardous conditions no longer exist.

(7) The following equipment requirements apply to special vehicle combinations:

(a) All trucks and truck tractors shall be powered to provide adequate acceleration ability and hill climbing ability under normal operating conditions, and to operate on level grades at speeds compatible with other traffic. The ability to maintain a minimum speed of 20 m.p.h. under normal operating conditions on any grade over which the combination is operated is required.

(b) All trucks and truck tractors shall have adequate traction to maintain a minimum speed of 20 m.p.h. under normal operating conditions on any grade over which the combination is operated and to be able to resume a speed of 20 m.p.h. after stopping on any such grade and to negotiate all grades encountered.

(c) Each individual single and tandem axle shall have tires of the same size and construction (radial or nonradial) . Tires must be properly inflated for the load being carried, and shall meet the standards set forth in 49 CFR section 393.75.

(d) All fifth wheels shall be clean and lubricated with a light duty grease. The fifth wheel shall be located in a position which provides adequate stability. The fifth wheel shall be heavy duty as required in 49 CFR section 393.70.

(e) Pick-up plates shall be of equal strength to the fifth wheel, as provided in 49 CFR section 393.70.

(f) The king pin shall be of a solid type and permanently fastened. Screw out or folding type king pins are prohibited.

(g) All hitch connections shall be of a no-slack type, preferably air actuated ram. Air actuated hitches, when used, must be isolated from the primary air transmission system.

(h) The drawbar length shall be the practical minimum consistent with weight distribution and clearances required between trailers for turning and backing maneuvers.

(i) Permanently attached trailer axles must be those designed for the width of the trailer.

(i) Truck-trailer-trailer combinations must have a minimum of six axles and a maximum of nine axles.

(ii) Truck tractor-semitrailer-trailer-trailer combinations must have a minimum of seven axles and a maximum of nine axles.

(j) All braking systems shall comply with state and federal requirements. In addition, fast air transmission and release valves shall be provided for all trailers, semitrailers, and converter dollies. A brake force proportioning valve may be provided on the steering axle. Indiscriminate use of engine retarder brakes is prohibited.

(k) Anti-sail mud flaps are required. If anti-sail mud flaps are not used, mud flaps and anti-spray and splash suppressant device systems are required.

(8) Special vehicle combinations are restricted to the following operating conditions:

(a) The total weight on any single axle may not exceed 20,000 pounds. The total weight on any tandem axle may not exceed 34,000 pounds. The total weight on any group of two or more consecutive axles may not exceed the amount provided in 61-10-107 , MCA.

(b) In no case may any trailer or semitrailer be placed in front of another trailer or semitrailer which carries an appreciably heavier load. The heaviest trailer or semitrailer shall be placed in front and the lightest at the rear. An empty trailer or semitrailer may not precede a loaded trailer or semitrailer.

(c) A special vehicle combination shall be stable at all times during normal braking and normal operation. A special vehicle combination, when traveling on a level, smooth, paved surface, shall follow in the path of the towing vehicle without shifting or swerving more than three inches to either side when the towing vehicle is moving in a straight line.

(d) While operating on a highway with two lanes in one direction, permitted vehicles shall remain in the right hand lane unless otherwise posted or conditions otherwise require, or when passing another vehicle or when emergency conditions exist.

(e) A minimum safe distance of 100 feet per 10 m.p.h. of speed shall be maintained between a special vehicle combination and other vehicles except when overtaking and passing.

(f) In the event a special vehicle combination is disabled for any reason other than an accident, it shall be parked as far off the traveled way as possible and marked as required by Federal Motor Carrier Safety Regulations.

(9) As required by 49 CFR section 177.835(c), transportation of Division 1.1 and 1.2 explosives is prohibited.

(10) A driver of a special vehicle combination shall be experienced in driving these combinations, maintain a good driving record and be subject to the following requirements:

(a) The driver shall comply with all of the driver's requirements of the Motor Carrier Safety Regulations of the U.S. Department of Transportation.

(b) The driver shall be under the control and supervision of the company holding the overlength permit.

(c) No person who has had any suspension of driving privileges in any state during the past three years where such suspension arose out of the operation of a motor vehicle used as a contract or common carrier of persons or property may operate a special vehicle combination.

(11) No person may operate any special vehicle combination under 61-10-124(4), MCA, at a speed greater than the posted speed limit. Violation of this restriction shall result in confiscation of permits.

(12) Every special vehicle combination operated under an oversize permit shall be covered by insurance of not less than $1 million combined single limit bodily injury and property damage liability per occurrence unless a greater amount is required by state or federal law or regulations.

(13) No overlength permit may be issued to a company which does not have a documented, established safety compliance program, including a driver training and certification program.

(14) Any company approved to operate special vehicle combinations under an overlength permit shall provide the Department of Transportation with any information relating to accidents, operational costs, safety inspections, equipment, maintenance, and other items which may be requested.

(15) Notwithstanding other state and federal requirements for reporting motor vehicle accidents, reportable accidents involving special vehicle combinations operated under a special overlength permit must be reported to the Montana transportation department within ten days of the date of the accident.

(16) The original permit shall be carried in the truck or truck-tractor of the special vehicle combination operating under the permit, and shall be displayed to any peace officer, employee of the Department of Transportation, Montana Highway Patrol upon request.

(17) In addition to the requirements in this rule, all equipment operated, all drivers employed and all operating procedures used shall comply with the current Motor Carrier Safety Regulations, parts 390 through 397 of the U.S. Department of Transportation, Federal Highway Administration.

(18) An overlength permit may be confiscated by any peace officer or by the Department of Transportation for failure of the company or any of its drivers to comply with any requirement contained herein.

(19) Application for permits may be obtained from the Department of Transportation, Motor Carrier Services Division, Box 4639, Helena, MT 59604, during regular business hours, Monday through Friday, except on legal holidays observed by the state of Montana.

(20) Complaints concerning operation of special vehicle combinations may be reported to the administrator of the Department of Transportation, Motor Carrier Services Division, P.O. Box 4639, Helena, MT 59604.

History: 61-10-129, 61-10-155, MCA; IMP, 61-10-124, MCA; NEW, 1987 MAR p. 1484, Eff. 8/28/87; AMD, 1996 MAR p. 1971, Eff. 7/19/96; AMD, 1998 MAR p. 171, Eff. 1/16/98; AMD, 2001 MAR p. 2142, Eff. 10/26/01; AMD, 2006 MAR p. 206, Eff. 1/27/06; AMD, 2012 MAR p. 1350, Eff. 7/13/12; AMD, 2016 MAR p. 312, Eff. 2/20/16.

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