The concept of trailer brakes is relatively simple: assist the tow vehicle in stopping the boat safely. However, the time to think about the effectiveness of trailer brakes — whether you have the stopping power to slow the vehicle and the boat and trailer package it is pulling — isn’t when you hit the road, it’s when you buy the boat or replace an old trailer.
What You Need to Know
Before autographing the paperwork that will make you a proud boat owner, take into consideration the total weight of the boat/motor/trailer package. And not just the dry or empty weight, but the weight of the package loaded and ready for the weekend, including fuel, food, batteries, gear, water and anything else that’s on the boat while it’s going down the road. Don’t forget to include the trailer itself in the calculations.
Then consult your local regulations. Many states require trailer brakes for packages above a certain weight. Some states require brakes on both axles on tandems and triples, while some only require brakes on one axle. More axles means more stopping power, so consider putting brakes on all wheels for added safety, even if that’s not required by state regulations.
Now ask yourself: Can my tow vehicle handle that weight? Check your owner’s manual or consult the dealer to verify that your vehicle is equipped to tow your new acquisition home. Some owners like to have brakes on smaller trailers if the loaded weight is near the maximum towing limit of the vehicle. There is a peace of mind knowing you aren’t taxing your vehicle to the limit, especially if mountainous trips with your boat are in your future.
Once you decide you need (or are required to have) brakes on your trailer, be sure they are the best style for your boating area. Brakes come in a number of different types and styles, some requiring extra equipment in the tow vehicle.
Types of Brakes
The least expensive brakes to install on the trailer are electric drum brakes. Boat trailer brakes need to be marine grade, and the electrical components have to be sealed against water intrusion. While less expensive when buying the trailer, electric brakes will require a brake controller at the dash of the tow vehicle, adding an expense if the tow vehicle isn’t already equipped. The brake controller automates the brakes so they work when the brake pedal of the tow vehicle is depressed.
Electric brakes should only be used in fresh water. Water and electricity don’t always get along, and saltwater immersion of the brake units will result in corrosion leading to brake breakdown. Electric brakes do have the advantage of being able to be controlled at the dash, so they can be manually activated if the trailer starts to sway, providing better control, especially going downhill. They also provide additional control when backing down the ramp, preventing a heavy boat package from pulling a lighter tow vehicle down the ramp.
Surge brakes are a better system for most applications. They use a brake actuator that is part of the trailer coupler, and the brakes are automatically engaged when the tow vehicle slows down; the weight of the boat pushing against the tow vehicle activates the brakes. More expensive than electric brakes, a surge system doesn’t require a dash-mounted controller, making the system simpler and able to be used on any vehicle.
For years, surge brake systems have been used successfully on trailers, usually with a drum-style brake assembly at the axle. Drum brakes are simple in operation and can be designed to freewheel in reverse, making it possible to back up the trailer with no extra effort on the operator’s part. Put the vehicle in reverse and the trailer backs up; however, a heavy boat package can exert a pulling force when backing down the ramp.
Recently, drum brakes have given way to superior disc brake technology. Disc brakes deliver superior stopping power and resist brake fade from constant use. Long downgrades on mountain passes will find disc brakes working as well at the bottom of the hill as the top. Drum brakes can lose effectiveness over long runs downhill.
Disc brakes have fewer moving parts than drum brakes, and the parts are exposed, which makes it easy to rinse the components. Disc brakes are self-cleaning on the braking surface and can be visually inspected without disassembly. For saltwater use, disc brakes are far superior to drums.
Disc brakes do have one disadvantage: They can’t be set up to freewheel in reverse. They don’t know which direction they are going. There is no left and right side like on drum brakes. To overcome this, manufacturers have lock-out solenoids installed on the trailer. Connected to the tow vehicle and triggered by its backup light, the solenoid prevents fluid from moving to the brakes and keeps them from activating.
For larger trailers carrying heavier boats, the best system is electric-over-hydraulic disc brakes. Such a system replaces the surge-activated brake solenoid with an electrically operated unit controlled by a brake controller in the cab. It has the benefits of electric brakes in that it permits cabin control of the brakes and allows for brakes while backing up.
It can be an expensive upgrade on smaller trailers but becomes more cost effective on larger tandem and triple units. With boat trailers capable of carrying boats weighing in excess of 15,000 pounds, electric-over-hydraulic is becoming an increasingly popular option for large boats on large trailers.
No matter what size boat you have or are considering, be sure to have the properly set up trailer under it that not only matches the boat but is a good match for your tow vehicle. Having enough power to get going down the road is only half the equation. Being able to stop it when you get there, or anyplace in between, is equally important.