Used Boat Trailer Buying Checklist

Boat owners can benefit greatly from owning a trailer. Storing the boat on dry land, whether in a secured parking lot or the backyard, is much cheaper than paying for a marina slip. In addition, your boat will be better preserved on a trailer and allow you to transport it to your new vacation destination with ease.

While buying a used boat comes with many risks, used boat trailers are a relatively safe purchase. With the simplicity of design in mind, boat trailers are rugged, durable, and can be used for decades. However, there are a few things to keep in mind when buying a used trailer, which we will elaborate on in this very article. 

Gross Weight

The first thing you should check is the gross weight limit of the trailer. Written on a sticker or metal plate, it will tell you whether or not the trailer is capable of hauling your boat’s weight. You should walk away from a trailer that doesn’t satisfy the weight limit, even if it appears to be an excellent deal.


Worn tires are usually not a significant expense. However, when you are buying a trailer, you want to minimize any additional costs. The largest trailers have up to four axles and eight wheels, but you are likely looking for a single or double axle model.

You can identify tire wear by cracked rubber, shallow treads, and widening at the base. Check the markings for the size and year the tires were manufactured. You can quickly check how much a new set would cost you by looking it up online and use it as a negotiation point. 

In practice, trailers have a much higher tolerance to wear than those mounted on cars. Being that a comfortable ride and braking capability are minimal factors, you can get by with older tires. In fact, some people tend to buy new tires for their car slightly ahead of time and place the used tires on the trailer. 

However, for trailers hauling heavy boats with an independent braking system, mounting new tires is highly recommended.

Wheel Bearings

While they are not an expensive part to repair, wheel bearing problems require immediate attention. Complete failure on the road will leave you stranded at best, or cause the wheel to lock up completely. Thus, it can result in a loss of control. Grinding or rumbling noise coming from the wheel indicates that the wheel bearings are beyond the point of safe use.


For single and double axle trailers meant for lighter boats, this section may not apply. Even so, every other type is likely to have some form of braking capability. State-by-state regulation may vary, but trailer brakes need to function flawlessly - both legally and for safety purposes. 

Testing the brakes on a trailer is no easy task. As they operate in tandem with towing vehicle brakes, it can be tough to tell whether the trailer brakes are applied. Trailer brakes come in two variants: surge or electric.

The same method for testing surge brakes can be used for the electric system. However, the reverse doesn’t apply. The trailer should be attached to the vehicle and lifted, either on supports or by hand, if it’s light enough. Spin the wheels by hand, and have someone apply the brakes inside the car. You will be able to hear and see the effects of the brakes to evaluate their condition correctly.


A functioning winch is necessary to pull the boat out of the water. Expand the winching cable and look for cracks or thinning. The connection point between the drum and the cable needs to be solid. To test out the functionality of the winch, you can have one or more people tug on the cable as you operate the winch. Alternatively, you can test it on a car set in neutral.

Trailer Jack and Parking Brake

When not attached to a vehicle, trailers are often stored leveled by a trailer jack. The jack should move smoothly and fully support the trailer, even under load. Some models are outfitted with a small wheel at the end of the jack, making it easier to roll the trailer and move it by hand. 

The parking brake is a large lever that works just like the one equipped in older automobiles. Simply pull the lever, then try to push the trailer. Perform this action a couple of times to see if the brakes are binding after being released. 


Rollers assist in the winching process and prevent contact between the boat and the metal parts of the trailer. Inspect each one for damage, and test if they roll. Problematic rollers will show uneven signs of wear.


Trailers are equipped with a leaf suspension, which is very durable. Even still, you should get underneath the trailer and see if there is any rust present, as this can be both a structural and safety hazard. Also, check if the trailer tilts to one side or another or if it squeaks under load. This is often indicative of a suspension that is due for replacement.

Electrical Components

The electric link between the vehicle and trailer sends power to the brakes and rear lights of the trailer. Once connected to the towing vehicle, one person should take a seat behind the wheel while another observes the lights. Test out brake lights, left and right indicators, and the nightlights to ensure that the trailer is safe and road legal. 


The coupling connects to the gooseneck or the fifth-wheel hitch and secures the trailer to the towing vehicle. It is arguably the most essential part of the trailer. Therefore, thoroughly inspect it for wear and damage. Once attached to the hitch, pull hard on it in an attempt to disengage it.