Generally, towing laws are left up to each individual state. Thus, it is important to do your homework before setting off on a journey across state lines. Before towing a trailer through the state of Pennsylvania, you should visit the Pennsylvania DMV website and familiarize yourself with Keystone State laws regarding towing.


Any trailer being towed in the state of Pennsylvania must be equipped with a fully functioning brake system. The brakes must apply to all four wheels. When the brakes are applied, the trailer must stop within a certain distance. Trailers weighing more than 3,000 pounds must have a breakaway system. Trailers with extra wheels must have a brake system on each extra wheel.


A trailer's tires must all be the same size, unless there is an emergency. Non-pneumatic tires are prohibited, and tires cannot have ice grips or studs applied that are more than 1/16 of an inch long. Drivers may not mix radial and belted tires on the same axis; all tires on an axis must be of the same type. Tires cannot touch any part of the trailer's main body, fenders or chassis.


A trailer must have at least one red light attached to the back that lights up when the brakes are applied. Trailers also are required to have rear lights, parking lights, turn-signal lights, hazard lights and stop lamps. All lights must be visible to the human eye from 500 feet away at night. A trailer's turn-signal lights must flash with a frequency between 60 and 120 flashes every minute. Trailers must have a small light that keeps the trailer's license plate illuminated at night.

Additional Regulations

A trailer that is higher than 30 inches off the ground must have a bumper. Each trailer should be outfitted with rear-wheel flaps that prevent the back tires from splashing debris into following cars. Trailers cannot be towed faster than 55 miles per hour on the highway. Trailers cannot be wider than 8 feet, 6 inches, and cannot be taller than 6 feet. The overall length of the car and the trailer connected cannot be longer than 60 feet.