Department of Revenue 
Motor Carrier Services Division
1 CCR 209-1
COLORADO DEPARTMENT OF REVENUE MOTOR CARRIER SERVICES DIVISION RULES AND REGULATIONS
 Rules for Size and Weight of Vehicles and Loads
Definitions

1.	Tandem Axle Two or more consecutive axles, the centers of which may be included between parallel vertical planes spaced more than 40 inches and not more than 96 inches apart, extending across the full width of the vehicle, all of which are in contact with the ground. If only one of a set of multiple axles is in contact with the ground, the configuration is not a tandem axle until it is actually used as such.

2.	Cargo The goods carried as freight by a commercial vehicle.

3.	Specialized Automobile  Transporter Any vehicle combination designed and used specifically for the transport of assembled highway vehicles, including truck camper units. The specialized automobile transporter will be designed to carry vehicles on the power unit behind the cab or on an over-cab rack. 

4.	Load Transference Device. Such device shall be permanently attached to the rear of another vehicle and shall be validly registered. In order to be considered a load transference device and therefore a separate vehicle, no such vehicle shall carry a gross weight of less than ten percent of the overall gross weight of the combination of vehicles. Such vehicle shall not be capable of hauling any portion of a load upon itself but shall be designed and utilized for transference of a portion of the total gross weight of another vehicle/load onto itself.

Vehicle Weight

1.	Wheel and Axle Loads

(a)	§ 42-4-507(3)(a) C.R.S. applies to vehicles using a single drive-axle configuration that are not operating on an interstate highway. Vehicles equipped with a self-compactor and used solely for the transporting of trash are not afforded the relief found in § 42-4-507(3)(a) C.R.S. if they are equipped with a tandem drive-axle configuration but not using the tandem drive-axle configuration. Vehicles equipped with but not using a tandem drive-axle configuration will be governed by the axle weight limitations provided in § 42-4-507(2)(b).

(b)	Vehicles equipped with a self-compactor and used solely for the transporting of trash that are equipped with and using a tandem drive-axle must comply with § 42-4-507(2)(c) C.R.S.

(c)	Any vehicle that utilizes an auxiliary power or idle reduction technology unit in order to promote reduction of fuel use and emissions because of engine idling, shall have the actual weight of the auxiliary power or idle reduction technology unit, up to 400 lbs., exempted from the calculation of actual axle weight. To be eligible for this exemption, the operator of the vehicle must be able to prove:
(i)  By written certification, the actual weight of the APU; and
(ii) By demonstration or certification, that the idle reduction technology is fully functional at all times.
Certification of the weight of the APU must be available to law enforcement officers if the vehicle is found in violation of applicable weight laws. The additional weight allowed cannot exceed 400 lbs. or the weight certified whichever is less.

(d)	Any over-the-road bus, or any vehicle which is regularly and exclusively used as an intrastate public agency transit passenger bus, is excluded from the axle weight limit found in § 42-4-507(2)(b), C.R.S. 

2.	Gross Vehicle Weight

(a)	The legal gross weight limit for a vehicle or combination of vehicles, as stated in § 42-4-508 C.R.S., shall be determined by the actual number of axles in contact with the road surface.

(b)	Where a vehicle in a combination of vehicles, does not carry at least 10 percent of the overall gross weight of the combination of vehicles as required in § 42-4-508(1)(c)(IV) C.R.S., the legal gross weight limit will be determined by the single vehicle weight limits found in §§ 42-4-508(1)(a)(II), 42-4-508(1)(a)(III), 42-4-508(1)(b), 42-4-508(1)(c)(I), 42-4-508(1)(c)(II), or 42-4-508(1)(c)(III) C.R.S., as determined by the number of axles utilized by the vehicle and the route traveled.

(c)	Any vehicle that utilizes an auxiliary power or idle reduction technology unit in order to promote reduction of fuel use and emissions because of engine idling, shall have the actual weight of the auxiliary power or idle reduction technology unit, up to 400 lbs., exempted from the calculation of actual gross vehicle weight. To be eligible for this exemption, the operator of the vehicle must be able to prove:
(i) By written certification, the actual weight of the APU; and
(ii) By demonstration or certification, that the idle reduction technology is fully functional at all times.
Certification of the weight of the APU must be available to law enforcement officers if the vehicle is found in violation of applicable weight laws. The additional weight allowed cannot exceed 400 lbs. or the weight certified whichever is less.

Vehicle Width

1.	Vehicle components not excluded by law or regulation shall be included in the measurement of the width of commercial motor vehicles.

2.	The following shall be excluded from the measured width of commercial motor vehicles, as applicable:
(a) Rear view mirrors, turn signal lamps, handholds for cab entry/egress, splash and spray suppressant devices, load induced tire bulge;

3.	Unless specifically included in a separate rule, the following devices are excluded from measurement of the width of a commercial motor vehicle, as long as they do not carry property and do not exceed 3 inches from the side of the vehicle. This list is not exhaustive:
(a) Corner caps;
(b) Hazardous materials placards and holders;
(c) Lift pads for trailer on flatcar (piggyback) operation;
(d) Rain gutters;
(e) Rear and side door hinges and their protective hardware;
(f) Side marker lamps;
(g) Structural reinforcement for side doors or intermodal operation (limited to 1 inch from the side within the 3 inch maximum extension);
(h) Tarping systems for open-top trailers;
(i) Movable devices to enclose the cargo area of flatbed semitrailers or trailers, usually called tarping systems (conestoga type trailers), where no component part of the system extends more than 3 inches from the sides or back of the vehicle when the vehicle is in operation. This exclusion applies to all component parts of tarping systems, including the transverse structure at the front of the vehicle to which the sliding walls and roof of the tarp mechanism are attached, provided the structure is not also intended or designed to comply with 49 CFR 393.106, which requires a headerboard strong enough to prevent cargo from penetrating or crushing the cab; the transverse structure may be up to 108 inches wide if properly centered so that neither side extends more than 3 inches beyond the structural edge of the vehicle. Also excluded from measurement are side rails running the length of the vehicle and rear doors, provided the only function of the latter, like that of the transverse structure at the front of the vehicle, is to seal the cargo area and anchor the sliding walls and roof. On the other hand, a headerboard designed to comply with 49 CFR 393.106 is load bearing and thus limited to 102 inches in width. However, the “wings” designed to close the gap between such a headerboard and the movable walls and roof of a tarping system are width exclusive, provided they are add-on pieces designed to bear only the load of the tarping system itself and are not integral parts of the load-bearing headerboard structure;
(j) Tie-down assembly on platform trailers;
	(k) Stake pockets;
(l) Wall variation from true flat; and
(m) Weevil pins and sockets on low-bed trailers (pins and sockets located on both sides of a trailer used to guide winch cables when loading skid mounted equipment).

4.	Each exclusion allowance is specific and may not be combined with other excluded devices.

Vehicle Length

1.	Vehicle components not excluded by law or regulation shall be included in the measurement of the length of commercial motor vehicles.

2.	Vehicle length is generally measured from front-most fixed point (generally front bumper) to rear-most fixed point (generally where brake lights are located.) Any truck with any permanently mounted appurtenance that projects beyond the front, rear, or both, of the vehicle the appurtenance is permanently mounted to, becomes a part of the vehicle and is included in overall vehicle length measurement. As such, the appurtenance is not considered overhang or a projection for the purposes of § 42-4-209 C.R.S., or § 42-4-504 C.R.S. 

3.	Drawbar or tongue lengths on trailers. 

(a)	Where the drawbar or tongue is of rigid construction, the measurement will be taken from the rear most point of the power unit's cargo box to the front most point of the trailer's main frame.

(b)	Where the drawbar or tongue is hinged, are to be measured as follows. The measurement will be taken from the rear most point of the power unit's cargo box to the front most point of the hinge.

(c)	A tool or accessory box welded to or carried on the drawbar or tongue does not factor into the calculation of drawbar or tongue length, due to the fact that a tool or accessory box is not designed to carry cargo.

4.	Pole trailers, primarily designed for the transportation of cargo, which have a flexible design and are operated without cargo, must have the connection between vehicles reduced to fifteen feet or less if the overall length of the vehicle combination exceeds fifty-five feet.

5.	All overall length provisions regarding specialized automobile transporters are exclusive of front and rear cargo overhang. Extendable ramps or “flippers” on specialized automobile transporters are excluded from the measurement of vehicle length, but must be retracted when not supporting vehicles. Extendable devices that are not supporting vehicles and have not been retracted will be included in the measurement of vehicle length.

6.	The following shall be excluded from the measured length of commercial motor vehicles, as applicable:
(a) Rear view mirrors, turn signal lamps, handholds for entry/egress, splash and spray suppressant devices;

7.	Unless specifically included in a separate rule, the following devices are excluded from measurement of the length of a commercial motor vehicle, as long as they do not carry property and do not exceed the dimensional limitations stated:
(a) All non-property-carrying devices, at the front of a semitrailer or trailer including: 
(1)	A device at the front of a trailer chassis to secure containers and prevent movement in transit;
(2)	A front coupler device on a semitrailer or trailer used in road and rail intermodal operations;
(3)	Aerodynamic devices, air deflector;
(4)	Air compressor;
(5)	Certificate holder (manifest box);
(6)	Door vent hardware;
(7)	Electrical connector;
(8)	Glad-hand;
(9)	Handhold;
(10)	Hazardous materials placards and holders;
(11)	Heater;
(12)	Ladder;
(13)	Non-load carrying tie-down devices on automobile transporters;
(14)	Pickup plate lip;
(15)	Pump off line on tank trailer;
(16)	Refrigeration unit;
(17)	Removable bulkhead;
(18)	Removable stakes;
(19)	Stabilizing jack (anti-nose dive device);
(20)	Stake pockets;
(21)	Step;
(22)	Tarp basket;
(23)	Tire carrier; and
(24)	Upper coupler

(b) Non-property-carrying devices (this list is not exhaustive) at the rear of a semitrailer or trailer that: 
(1)	Do not extend more than 3 inches beyond the rear of the vehicle, or
(2)	Do not extend more than 24 inches beyond the rear of the vehicle and are needed for loading or unloading, or
(3)	Resilient bumpers that do not extend more than 6 inches beyond the rear (or front) of the vehicle;
(4)	Aerodynamic devices that extend a maximum of 5 feet beyond the rear of the vehicle,
(5)	Handhold;
(6)	Hazardous materials placards and holders;
(7)	Ladder;
(8)	Pintle hook;
(9)	Removable stakes;
(10)	Splash and spray suppression device;
(11)	Stake pockets; and
(12)	Step.

8.	Each exclusion allowance is specific and may not be combined with other excluded devices.

Vehicle Height

1.	The Department of Transportation designation of maximum height limits shall be as  
designated on the Department’s Height Restriction Map.