Braking Systems

The selection of a brake system also will depend on your tow vehicle and the type and fully loaded weight of your trailer. For a trailer with a loaded weight of more than 1,500 pounds, many states require a separate braking system and a breakaway switch, located on the tongue of the trailer, to activate the trailer brakes in the event the trailer separates from the tow vehicle. There are two basic types of brake systems designed to activate the brakes on a trailer: 

• Electronically controlled brakes usually provide automatic and manual control for trailer brakes. They require that the tow vehicle be equipped with a controlling device and additional wiring for electrical power. These brakes typically have a control box installed within reach of the driver and can be manually or automatically applied. The control box may require adjustment or “tuning in” for variations in trailer load. 
• Surge brakes are independent hydraulic brakes activated by a master cylinder at the junction of the hitch and trailer tongue. These brakes are not controlled by the hydraulic fluid in the brake system of the tow vehicle. Note: The hydraulic system of the tow vehicle should never be directly connected to the hydraulic system of the trailer. These systems are self-compensating and do not require adjustment for variation in trailer load.  Follow the tow vehicle manufacturer’s recommendations for brake selection. Some states require braking systems on all axles of the trailer. So, check your state’s requirements by contacting the motor vehicle administration.