Your #1 Source for Trailer Hitch Information


What is a trailer hitch? Trailer Hitch on SUV

A trailer hitch, also called a receiver hitch or hitch receiver, is a metal weldment that is attached to the back undercarriage of a vehicle for the purpose of towing a trailer or transporting a hitch rack. The trailer hitch consists of a square receiver tube into which you can insert any number of ball mounts (for towing) or hitch mounted racks for carrying bikes or gear. Trailer hitches are typically specific to the year, make and model of a vehicle.

Trailer hitches are classified into 5 classes based upon their towing and tongue weight capacities. Not all hitches can be mounted to all vehicles. It is essential that you follow the hitch guidelines provided by your vehicle manufacturer.

Trailer Hitch Classes

There are 5 classes of trailer hitches, each specifying maximum Gross Towing Weight (GTW) and Tongue Weight (TW) capacities. Class 1 and 2 hitches are for cars, smaller SUV's, and small trucks. Class 3,4, and 5 are used on larger minivans, pickups, SUV's, and almost all RV's. Use the following chart to see which hitch receiver will typically work on your vehicle:


Trailer Hitch Classes


Gross Trailer Weight (GTW): is the weight of the trailer and cargo. Measure this by putting the fully loaded trailer on a vehicle scale.

How to measure gross trailer weight

Tongue Weight (TW): The downward force that is exerted on the hitch ball by the coupler. The tongue weight will vary depending on where the load is positioned in relationship to the trailer axle(s). To measure the tongue weight, use either a commercial scale or a bathroom scale with the coupler at towing height. When using a bathroom scale with heavier tongue weights, use the method shown and multiply the scale reading by 3.

How to calculate tongue weight capacity

Trailer Hitch Sizes

Trailer hitches come in three sizes: 1.25 inch, 2 inch, and 2.5 inch square receivers. Class 1 and 2 hitches, designed for smaller vehicles, most frequently have a 1.25 inch square receiver tube. Class 3 and 4 hitches always have a 2 inch square receiver while Class 5 hitches generally have a 2.5 inch square receiver. Many hitch bike racks and hitch cargo carriers require a 2 inch trailer hitch, so if you have a smaller vehicle, make sure your bike rack or cargo carrier is compatible with your receiver hitch.


Choosing a Trailer Hitch

Start by determining the towing and tongue weight capacities of the vehicle on which you will be installing the hitch. This information is available in the owner's manual or from your dealer.

Once you know your vehicle's hitch capacities you might consider these factors in making your final hitch selection.

  • What is the gross towing weight of anything you will be towing?
  • What are the tongue weights of anything that you will be towing or carrying in your hitch (like a bike rack or cargo carrier)?
  • Do you have a bike or cargo rack that only fits a 1.25 inch or 2 inch receiver hitch?
  • Do you have a styling preference for round tube over the traditional square tube hitch? (The receiver tube is always square)

Note: Your towing and tongue weight capacities will be determined by the rating of your vehicle or by the rating of the trailer hitch, whichever is lowest. Installing a Class 4 hitch on a small vehicle will not increase the towing capacity of that vehicle.

To find specific hitch choices for your vehicle, it is best to use a Trailer Hitch Finder such as the one found on You simply input your vehicle year, make, model and style and the finder will present your hitch options. offers U.S. Made CURT Hitches which are available in black or in colors (optional) to match your vehicle.

Trailer Hitch Add-Ons

The most popular add-on for a trailer hitch is a wiring kit to enable you to plug in trailer lights. Wiring kits are vehicle specific and can be found via the Trailer Hitch Finder referenced above. Not all vehicles lend themselves to a self installed wiring kit, in which case you should contact your dealer about a custom wiring kit installation.

Installing a Trailer Hitch

Most receiver hitches are designed to be bolted to the frame of the vehicle. On many vehicles the necessary bolt holes already exist, but on others, the holes must be drilled. The installation time for a typical hitch will take 30-60 minutes with an additional 30 minutes for the wiring kit. CURT hitches come with excellent instructions for both hitch and wiring installation.

Note: The tables and images were provided by CURT Manufacturing.