Truck and trailer rules in Connecticut: licence line, brakes, towing, size and weight limits

This page reports what the official source says. It is not legal advice: ask the office named here. The sources are chapters 246 and 248 of Title 14, Motor Vehicles, of the Connecticut General Statutes, published by the Connecticut General Assembly, and the Connecticut Department of Motor Vehicles commercial driver license page. Federal background and the other places are on the parent page, trucks and trailers for tree work.

At a glance

Item	What the sources say
Commercial motor vehicle	Rated 26,001 pounds or more, including a towed unit over 10,000 pounds; 16 or more passengers; placarded hazardous materials
Class A	Combination rated 26,001 pounds or more, towed vehicle over 10,000 pounds
Class B	Single vehicle rated 26,001 pounds or more, or towing a vehicle not over 10,000 pounds
Brakes	Service and parking brake systems; vehicles of 10,000 pounds or more must meet 49 CFR part 393 subpart C
Width, height	Permit above 102 inches wide; permit above 13 feet 6 inches high
Length	45 feet single unit; 48 feet semitrailer; permit above 65 feet for a truck and trailer
Weight	22,400 pounds single axle; 80,000 pounds gross on a compliant combination

The commercial vehicle line and licence classes

Section 14-1 defines a commercial motor vehicle as a vehicle designed or used to carry passengers or property, other than a vehicle used for farming under 49 CFR 383.3(d), fire fighting apparatus, an emergency vehicle or a recreational vehicle in private use, that has a gross vehicle weight rating of 26,001 pounds or more, or a gross combination weight rating of 26,001 pounds or more including a towed unit rated over 10,000 pounds. It also covers a vehicle designed for 16 or more passengers including the driver, and one designed for more than ten passengers that carries students under 21 to and from school. Section 14-44d sets the classes. Class A is any combination with a rating of 26,001 pounds or more where the towed vehicle is rated over 10,000 pounds. Class B is any single vehicle rated 26,001 pounds or more and any such vehicle towing a vehicle not over 10,000 pounds. Class C is a single vehicle rated under 26,001 pounds, or towing a vehicle not over 10,000 pounds, that is built for 16 or more passengers or carries placarded hazardous materials. The Connecticut DMV commercial driver license page repeats the 26,001 pound, 16 passenger and placarded hazardous materials lines and lists the exempt vehicles as farm vehicles within 150 miles of the farm, fire-fighting apparatus, authorized emergency vehicles, recreational vehicles and military vehicles operated by military personnel. See chapter 246 on motor vehicles.

Brakes

Section 14-80h requires each motor vehicle other than a motorcycle to have at least two braking systems, a service brake system and a parking brake system, each with a separate means of application by the operator and kept in good working order. The service brake system must act on all wheels except as 49 CFR 393.42 provides, and the parking brake system must hold the vehicle or combination stationary under any loading on any grade where it is operated. No one may operate a vehicle with a gross vehicle weight or rating of 10,000 pounds or more with a braking system that fails the standards in Subpart C of 49 CFR part 393, and the section sets a fine of not less than US$250 and not more than US$500 for that. The section does not apply to a pole trailer, and it sets no trailer weight line of its own.

Towing, width, height and length

Section 14-261 says that when an occupied vehicle is towed, the distance between the towing and towed vehicle may not exceed 20 feet, and a rigid tow bar must be used on a limited access highway and for any unoccupied vehicle. No person may tow more than one vehicle at a time, with exceptions including a vehicle towing a non-cargo-carrying vehicle of up to 5,000 pounds gross when the overall length does not exceed 55 feet.

Section 14-262 requires a special written permit from the Commissioner of Transportation for a vehicle or combination wider than 102 inches with its load, with exceptions that include farm equipment, a vehicle loaded with hay or straw and a vehicle with an attached snow plow up to 144 inches wide. Reasonably sized mirrors, turn signals, steps and handholds, and spray suppressant devices are left out of the width, provided no safety device protrudes more than three inches from each side. It also requires a permit for a truck and trailer combination longer than 65 feet, with exceptions such as tractor-trailer units. The maximum length of a single unit vehicle including load is 45 feet, and of the semitrailer portion of a tractor-trailer unit 48 feet, with trailers up to 53 feet allowed on listed routes. A fine of US$500 applies. Section 14-264 requires a permit for a vehicle with its load higher than 13 feet 6 inches, except one loaded with loose hay or straw, with a fine of US$1,500.

Weight

Section 14-267a says axle weight and gross weight, including load, may not exceed the lesser of the manufacturer's rating or the statute's limits. A single axle may carry 22,400 pounds, or 18,000 pounds on each axle where axles are spaced less than six feet apart. A two-axle vehicle may not exceed 36,000 pounds gross, a three-axle vehicle 53,800 pounds and a three-axle combination 58,400 pounds. A four-or-more-axle vehicle or combination may not exceed 67,400 pounds, or 73,000 pounds where the distance between the first and last axle is at least 28 feet. A vehicle or combination with a semitrailer may run without a written permit at up to 80,000 pounds if it meets the single axle limit, the federal-aid highway amendments of 1974 and a weight distribution formula. Pneumatic tires may carry not more than 600 pounds per inch of tire width. See chapter 248 on vehicle highway use.