Towing Hitch Classes Explained – Choosing the Right Trailer Hitch Ball Sizes

A trailer hitch is a device attached to the chassis of a vehicle and gives the vehicle towing capabilities. There are several types of trailer hitch assemblies, but the most common hitch is typically a tow ball attachment. The trailer hitch ball allows the hitch to swivel and tow a trailer safely. The vehicle has a trailer hitch ball while the trailer has a hitch component that fits over the ball. The hitch receptacle has to be sized to fit the ball or the hitching system will not be effective.

Trailer hitch balls are available in different sizes depending on the application and the vehicle to which it will be attached. It is essential to have a trailer hitch ball installed by a qualified installer. When it comes to trailer hitch balls, there is no such thing as “one size fits all.”

The trailer hitches, of which there are four classes, have been defined by the SAE (Society of Automotive Engineers) based on the weight of the trailer and the cargo and the Gross Weight Towed Weight Rating (GTWR). It is important to note the weight a vehicle can tow is not determined by the class of hitch attached to the vehicle. It is determined by the suspension of the vehicle, the engine’s horsepower, and its cooling system. The towing capacity of a vehicle can be found in the vehicle manual or by contacting the vehicle manufacturer. Attaching a class IV hitch to a passenger car will not make it capable of towing 9,900 pounds.

Much like in boxing, the weight class of your vehicle’s towing capability will reign supreme as you angle to select your trailer hitch. There are four different towing hitch classes that are commonly used and we’ll break those down for you.

Hitch Class 1

The first hitch class on our list is probably the most common, as it is found on most sedans and small trucks. Hitch Class 1 means that your car can tow up to 2,000 lbs for the GTW. What is the GTW you ask? That would be the Gross Trailer Weight, meaning the loaded-to-the brim option. At 2,000 lbs you aren’t going to be towing anything more heavy-duty than a motorcycle or smaller jet ski, so don’t even think of trying to hitch a trailer to this lightweight ride.

Hitch Class 2

The second class you’ll come across is Hitch Class 2 and it means that your vehicle is rated up to 3,500 lbs GTW. This is the class that most Subaru Outback models are rated at. To be specific: your Outback will range anywhere from 2,700 lbs to 3,000 lbs in towing capability. Reference your owner’s manual or contact your manufacturer in order to find your exact weight class. At nearly 3,500 lbs you are able to hitch a smaller trailer or boat.

Hitch Class 3

Now we are into the heavy-duty section of the different hitch classes around. Hitch Class 3 puts your GTW up to a stunning 8,000lbs which allow you to hitch fishing boats and larger trailers. If you are in this class then you probably have a pretty rugged vehicle.

Hitch Class 4/5

The final class we’ll mention blends the 4/5 marker. At this rate, you can tow up to 18,000lbs GTW and you can do it pretty efficiently. This is the standard class for those trucks you see hauling around travel trailers on the highway.

It is essential to make sure the trailer ball hitch is properly installed on the vehicle to assure safe and effective towing. It does not matter the distance a trailer will be towed the right size hitch and installation will be the difference between successful towing and just good enough towing. It is important the trailer hitch is fitted to the vehicle and trailer precisely and made from quality materials. Installing a trailer hitch is not a retrofit job from whatever materials can be found in the garage or cellar workshop.

There are specifications and standards that control the quality of the trailer hitch and installation. Vehicle Equipment Safety Commission V5 (VESC V5) regulation provides specifications for the weights of the four light hitch classifications, breaking strengths of hitch components, safety chain attachment procedures as well as installation standards. It is not necessary to know the regulations chapter and verse, but it is important the trailer hitch and installation meet the requirements. Keep in mind, each state may have standards that differ from VESC V5. Typically, it is appropriate to adhere to the most stringent regulation.

Before installing a trailer hitch ball it is necessary to know what type of load and trailer to be towed. Most trailers are utility trailers and the load may be something like tools, bicycles, camping equipment or furniture. The trailer may also hold a boat, ski-mobile, off-road vehicle or appliances. The limit to what a trailer will hold will be limited by the size and carrying capacity of the trailer and the towing capacity of the vehicle. When towing a trailer it is essential to load the trailer carefully, dispersing the weight of the contents equally. This will allow the hitch assembly to function as it should and not compromise the hitch ball integrity, trailer or vehicle. A compromised hitch assembly, trailer or vehicle could create an unsatisfactory safety condition.