Truck and trailer rules in Delaware: licence classes, trailer brakes, 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 three chapters of Title 21, Motor Vehicles, of the Delaware Code, published by the Delaware General Assembly: chapter 26 on the Uniform Commercial Driver License Act, chapter 43 on equipment and construction of vehicles and chapter 45 on size and weight of vehicles and loads. 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	Combination rated 26,001 pounds or more with a towed unit over 10,000 pounds; vehicle rated 26,001 pounds or more; 16 or more passengers; any size carrying hazardous materials
Class A	Combination rated 26,001 pounds or more, towed unit rated over 10,000 pounds
Class B	Single vehicle rated 26,001 pounds or more, or towing a vehicle not over 10,000 pounds
Trailer brakes	Trailer or semitrailer over 4,000 pounds gross needs brakes controlled from the towing vehicle above 10 miles per hour
Width, height	8 feet 6 inches (102 inches); 13 feet 6 inches
Length	40 feet single vehicle; 60 feet combination off the interstate; 53 feet semitrailer on it
Weight	80,000 pounds at 5 or more axles; 20,000 pounds single axle on the interstate

The commercial vehicle line and licence classes

Section 2603 of chapter 26 defines a commercial motor vehicle as a motor vehicle or combination used in commerce to carry passengers or property that has a gross combination weight rating of 26,001 pounds or more including a towed unit rated over 10,000 pounds, has a gross vehicle weight rating of 26,001 pounds or more, is designed to carry 16 or more passengers including the driver, or is of any size and carries hazardous materials. Section 2611 sets the classes. Class A is any combination with a gross combination weight rating of 26,001 pounds or more, provided the rating of the towed unit is more than 10,000 pounds. Class B is any single vehicle rated 26,001 pounds or more, or one towing a vehicle not over 10,000 pounds. Class C is a single vehicle or combination 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. Endorsements run from H for hazardous materials and T for double and triple trailers to P for passengers and N for tank vehicles. See chapter 26 on the commercial driver license act.

Brakes

Section 4303 of chapter 43 requires every motor vehicle on a highway to have brakes adequate to control, stop and hold it and any trailer or semitrailer attached, with two separate means of applying them, each effective on at least two wheels. Section 4304 requires service brakes able to stop a vehicle or combination travelling 20 miles per hour within 30 feet on dry level pavement, and the hand brake within 55 feet, and holds a two-wheel-brake vehicle to 40 feet. Those distances apply whether or not the vehicle carries the most chapter 45 allows. Section 4305 says no trailer or semitrailer with a combined gross weight of vehicle and load over 4,000 pounds may be operated at more than 10 miles per hour unless it has suitable brakes controlled by the operator of the towing vehicle. See chapter 43 subchapter I on equipment requirements.

Size and weight off the interstate

Section 4502 sets the size and weight limits for roads, streets and highways in the State except as section 4503 provides. No vehicle with its load may exceed 8 feet 6 inches in width or 13 feet 6 inches in height. A single motor vehicle with its load may not exceed 40 feet in length and a combination 60 feet, with named exceptions such as pole trailers and indivisible loads up to 70 feet. Section 4501 limits the authorized combinations to a truck and trailer, a truck tractor and semitrailer, a truck tractor with semitrailer and trailer, a saddlemount vehicle string and a tow truck with a disabled vehicle. It also says the State need not raise any structure for a vehicle higher than 12 feet 6 inches, and that the owner or operator bears the liability for damage such a vehicle causes.

Section 4502 sets gross weight by axle count where each axle has two hubs with a power brake on each hub. A 2-axle vehicle may not exceed 40,000 pounds, a 3-axle vehicle 65,000 pounds and a 4-axle vehicle 73,280 pounds, or the manufacturer's gross vehicle weight rating if lower. A tractor and semitrailer with 3 axles may not exceed 60,000 pounds, with 4 axles 70,000 pounds and with 5 or more axles 80,000 pounds. No axle load may exceed 22,400 pounds, and a combination's two consecutive axles spaced 96 inches or less but not under 40 inches apart are limited to 36,000 pounds.

Size and weight on the interstate

Section 4503 sets size on the interstate, federal-aid primary highways and United States numbered routes, and says its weight limits apply only to the interstate, with the other two following section 4502. Height is 13 feet 6 inches. A semitrailer may be 53 feet, a trailer or semitrailer in a tractor-semitrailer-trailer combination 29 feet, a single vehicle 40 feet and a bus 45 feet. Width is 102 inches, with safety equipment allowed to add no more than 3 inches on each side. On the interstate, weight on one axle may not exceed 20,000 pounds, on tandem or coupled axles 34,000 pounds, and gross weight is capped by axle count: 40,000 pounds on 2 axles, 54,000 on 3, 74,000 on 4 and 80,000 on 5. The section also gives a formula for groups of consecutive axles. See chapter 45 on size and weight of vehicles and loads.