Trailer brakes and their hub assemblies are the spinning components that connect the pavement to the axle. Along with their small mounting components as well as tires and wheels, they complete the trailer and make it road-ready. Like all other components in our Trailer Parts section, there are many weight and size options when it comes to brake assemblies. There are 2 questions that need to be answered so that you can install the correct brakes:

1. Given the size of the trailer, do we need to use brakes?
   Throughout Canada and the U.S., there are varying laws in place regarding towing practices - depending on the State or Province. Since most RV', Campers, and trailer Tow-ers travel over several States/Provinces, it is always safest to go with the average-to-stringest laws as a guideline for any given setup.

2. What are the brake style options available, and which is the best choice?
   There are 4 main choices when it comes to selecting a trailer brake style - meaning, choosing how you want the brakes to operate.
   - What each style is good at: Benefits & Features
   - How they work: Components
   - What gets done to the trailer: Brake Installation Process
    

Trailer brakes ensure that when a tow-vehicle is travelling down the road and puts on the brakes, the vehicles brakes are not doing the stopping for both the car and the trailer. This becomes more important the heavier the trailer that is being towed. A vehicles brakes are simply not designed to stop the vehicle PLUS an additional 3,500 lbs. (or more) behind it.

Electric Brake Assembly

Electric trailer brakes are the most common on the road today. Here is an Electric Brake Assembly (a.k.a "backing plate")

Almost all Electric Brakes are created equal. There is very little, if any, variance between options and features: they are basically just designed to stop the trailer wheels from turning, and they all do it the same way.

Manufacturers: There are several manufacturers making reliable backing plates, including Dexter. Brand is very important when trying to replace old backing plates or components, since there is no industry standard governing specs like the size or shape of a brake magnet. So more manufacturers have innovated their own designs. Overall, Dexter is the industry leader and the most common brand.

Finishes: In most brands, the backing plate is constructed of unfinished steel. There are however brands who specialize in marine applications. This is for boat trailers, where the brakes will be exposed to the corrosive effects of salt water. To slow the corrosion of steel components they are coated with a protective material that provides a barrier against solvents, heat and salt. They follow the same standard sizes as regular backing plates.

Components: How Electric Brakes Work

Take a look at the major parts that make up a brake assembly:

The large center circle represents the hole through which the Spindle goes, so we can install the backing plate on the axle. The 4 smaller holes represent bolt holes which are used to bolt the backing plate onto the Brake Flange which sits behind the spindle.

How does electricity make this brake work? The magnet in the backing plate has 2 conductor wires which tap directly into the trailer wiring. When electricity is on, it magnetizes the brake magnet. The magnet is attracted to the drum face. When it contacts this area, the friction causes it to rotate, which moves the actuating arm, and pushes the shoes out against the drum. Those shoes have a special brake pad material on them that resists the heat caused by that friction. When the shoes press against the inside of the drum, they prevent the hub, and consequently the wheel that's touching the ground from spinning.

How DOES the electricity get to the trailer brakes? Where does it come from? How do we know which brake to use? Here's how it works: An electrical connection on the trailer plugs into the connector on the vehicle. There are electrical wires running from the trailer connector back to each brake on the axle, as well as to the trailer lights, to create a complete circuit. When the driver steps on the brakes it sends a current to the brake control in the vehicle. The brake control then sends a current back to the trailer to activate the brakes. Here's what that looks like:

Brake Selection Process: It is not difficult to figure out the right Electric Brake for an application. Here are the steps:

1. Determine/Select the size of the brake needed
   - If it's a replacement brake, then measure the diameter of the original backin plate, also measure the width of the lining
   - If this brake is for a new axle, determine the capacity of the axle and find the matching capacity brake
    
2. Determine/Select the manufacturer of the brake
   - If its a replacement brake, check the original backing plate for identification points: part#, style, etc
   - If the trailer owner is building new - is there a brand/feature preference

Backing plates are named after their size and capacity. The dimension is for diameter of the backing plate, the second is for width of the shoes: 10" x 2-1/4"

The magnet wire colour will also be given. This helps identify two backing plates which are the same size, but different capacities. Backing plates are also distinguished between LEFT and RIGHT.

NOW THAT YOU KNOW HOW TO CHOOSE AN ELECTRIC BRAKE CONTROL, CLICK HERE TO CHOOSE THE CORRECT ONE FOR YOU. If you need help selecting Electric Brakes please contact us via Live Chat, Email, or call 800-300-4067 -hitchweb Team.