Shopping for a boat trailer can be daunting. You have to make myriad decisions. Take a look at this list, which provides a synopsis of the features you need to look for when buying a trailer for your boat or assessing the value of a trailer that comes with a new boat.
Size
The gross vehicle weight rating (GVWR) is the maximum weight the trailer is rated to carry. Include boat and engine weight, as well as your normal complement of gear and fuel, when considering size. For safety, add 15 percent more weight.
Single Axle
Trailers with one axle can cost less and require less maintenance than dual-axle trailers. They are also easier to move “manually” around driveways and into garages or other tight spots.
Multiple Axles
Trailers with two or more axles may cost more and require more maintenance. They are difficult to manually push and pivot into tight spaces. Multiaxle trailers will track better on the road and prove safer if a tire blows out.
Lights
LED lights are more durable and waterproof than incandescent lighting and tax your tow vehicle’s electrical system less (translation: you have brighter lights). Look for trailers with light brackets that protect the fixture versus those with exposed light fixtures.
Tires
Radial tires are better than bias-ply tires. Bias-ply tires transmit sidewall flex to the tread, increasing the chances for slipping. Bias-ply tires also present a smaller footprint, resulting in less grip on the road.
Frame
Galvanized steel is strong and corrosion-resistant for coastal boats, yet heavy and more expensive than a painted trailer. Painted-steel trailers are fine for freshwater use. Aluminum trailers offer great corrosion resistance with somewhat lighter weight and a high degree of aesthetic appeal.
Brakes
Electric brakes offer low maintenance and the ability to brake the trailer prior to the tow vehicle, which is handy going downhill. However, we do not recommend them for saltwater application. Surge brakes, though more complex, will prove more reliable in marine service.
Brakes II
While laws vary by state, we, along with many trailer manufacturers, recommend that multiaxle trailers have brakes installed on all axles.
Springs
Torsion axles can provide a smoother ride and require less maintenance, though they are not readily repairable. Leaf springs better absorb the load from uneven ground or shock from a pothole, especially on multiaxle trailers. Leaf springs are readily repairable but require more maintenance.
Bunks
Bunk trailers can be less expensive, though they may also prove harder to launch from and load a boat onto at a ramp with a shallow angle or a low water level. The addition of glides can obviate this somewhat. Bunk maintenance is minimal. Some builders of boats with cored hulls require the use of bunk trailers for warranty.
Rollers
Roller trailers may be more expensive, though they will likely prove easier to launch from and load a boat onto at a ramp with a shallow angle or low water level. Rollers require more maintenance than bunks. Boats with stepped hulls and pontoon boats may not be able to be launched with roller trailers.
Wiring
Look for tinned-copper wiring, especially if you will be in coastal waters. Heavy grommets and chafe protection should be used where wires enter and exit the trailer frame. Look for solid and accessible ground (white wire) points.
Bearing Lube
Traditional greased bearings are (relatively) easy to repair on the road. Oil bath bearings run cooler and with less friction, but they can develop condensation in the hubs if not used regularly and they’re not as easily repairable. Most boaters are better off with grease-packed hubs.
Trailer Tips
Grossed Out
Don’t confuse the gross axle weight rating (GAWR) with the gross vehicle weight rating (GVWR). The GAWR is for each axle. The GVWR is for the entire trailer.
Rinse Protection
When using acid-base hull cleaners, be sure to cover the trailer fenders with a tarp, lest the dripping cleaner remove the zinc galvanized coating or paint.
No Alternative
Do not substitute auto tires for trailer tires: Trailer tires have thicker sidewalls.
A Dry Bunk
Install hard plastic glides when using aluminum boats on a bunk trailer. Carpeted bunks hold water next to the aluminum and can corrode the metal.