3.3 Performance. Vehicle performance requirements, as specified in 3.3.1 through 188.8.131.52,
shall be met by the trailer when fully equipped, completely serviced, with payload uniformly
distributed over the trailer load area, and when towed by a towing vehicle over improved and
unimproved, hard, uneven terrain. The vehicle shall show no evidence of failure or malfunction of
trailer, trailer components, attachments, and accessories.
* 3.3.1 Towing speed and tracking ability. When transporting the rated payload, while being
towed over dry, level, smooth, improved, and prepared hard-surfaced roads at sustained speeds to
60 miles per hour (mph), and over dry unimproved and gravel roads at speeds up to 10 mph, the
trailer shall follow the towing vehicle without exceeding the tracking deviations as specified in
Federal Motor Carrier Safety Regulation 393.70(a).
3.3.2 Turning ability. When coupled to a towing vehicle operating in its minimum turning
circle, the trailer shall follow without cramping. The trailer shall be capable of moving through an
angle of not less than 60 degrees in relation to the towing vehicle without interference between
vehicles. The angle shall be measured between the longitudinal axis of the trailer and the
longitudinal axis of the towing vehicle at the coupling device.
3.3.3 Suspension systems. The axle, springs, accessories and components of the suspension
system shall withstand the imposed loads without evidence of permanent set, part failure or
malfunctioning under the operating conditions specified.
3.3.4 Brakes. The service brakes of the trailer, in conjunction with the towing vehicle (truck-
trailer combination), under all conditions of loading, shall control, decelerate, and stop the vehicle
combination in accordance with Federal Motor Carrier Safety Regulation 393.52.
184.108.40.206 Parking brakes. The parking brakes shall hold the fully loaded trailer on a dry, hard
surfaced grade of not less than 30 percent when uncoupled from the towing vehicle, resting on the
landing leg and running gear, and headed up and down the incline. The parking brake lever shall
have sufficient moment arm to require not more than 30 pounds of effort for application and
220.127.116.11 Automatic actuation. The trailer shall be equipped with an automatically actuated
device to apply the vehicle brakes upon breakaway from the towing vehicle. The breakaway
system shall conform to Federal Motor Carrier Safety Regulation 393.43.
3.4 Payload and distribution. The minimum payload shall be 2,000 pounds. Requirements
shall be met with the payload uniformly distributed over the loadspace.