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Parts of a Trailer Hitch

Chapter 2

Parts of a Trailer Hitch - Towing 101 - CURTParts of a Trailer Hitch - Towing 101 - CURT

Essential Towing Equipment for Pulling a Trailer

There are several different components needed for towing any type of trailer. A towing system is made up of the vehicle, trailer, and the equipment used to connect them.

In this guide, we will answer some basic questions about what a towing system is. What is a trailer hitch? What is a trailer? What equipment is required to be on a trailer? And much more!

Parts of a Trailer Hitch Diagram

Dinghy towing your vehicle? Check out our complete checklist of dinghy towing equipment!

What Is a Trailer HitchWhat Is a Trailer Hitch

9 Parts in a Towing System

1. What is a trailer hitch

Hitch definition: A trailer hitch is the primary connector between a tow vehicle and trailer. It is the structural component that bolts onto the vehicle and provides a coupling point to hook up a trailer.

When you think trailer hitch, you might picture what is actually referred to as a ball mount. A ball mount, however, is simply an accessory for a trailer hitch.

What is a Trailer Hitch - DiagramWhat is a Trailer Hitch - Diagram
What Is a Receiver HitchWhat Is a Receiver Hitch

What is a receiver hitch?

A receiver hitch is a type of trailer hitch that bolts onto the underside of a vehicle, at the rear, and provides a tube for attaching a ball mount or other hitch accessory. Receiver hitches generally have a vehicle-specific design, a standard receiver tube size and fall within one of five hitch classes.

A receiver hitch is perhaps the most common type of trailer hitch. So common, in fact, that the two terms are used interchangeably.

What is a tow hitch?

A tow hitch is simply another name for a trailer hitch. It is a hitch used for towing a trailer.

Usually, tow hitch refers specifically to a receiver hitch. However, a 5th wheel hitch, gooseneck hitch and other hitches may be called tow hitches. All trailer hitches -- or tow hitches -- are designed for a specific use and rated for specific weight capacities.

Need help selecting a trailer hitch?

What Is a Tow HitchWhat Is a Tow Hitch

What Is a Ball MountWhat Is a Ball Mount

2. What is a ball mount?

A ball mount is a receiver hitch accessory comprised of a shank and a trailer ball platform. The shank inserts into the hitch receiver tube, while the platform provides a solid mounting point for a trailer ball.

A ball mount is one of the most common trailer hitch parts.

Ball mounts come in a variety of styles and capacities. Some are fixed, made up of a single piece. Others are adjustable. Virtually all ball mounts come with a hole in the shank to accept a hitch pin or hitch lock.

What Is a Ball Mount - DiagramWhat Is a Ball Mount - Diagram
What Is a Ball HitchWhat Is a Ball Hitch

What is a ball hitch?

A ball hitch is another name for a ball mount. It is a receiver hitch accessory that provides a connection for hooking up a trailer.

A ball hitch refers more specifically to a ball mount with a trailer ball already attached. While some ball mounts come with only a platform and a hole, others have a trailer ball pre-torqued or welded into place. At CURT, we call these "loaded" ball mounts.

What Is a Trailer BallWhat Is a Trailer Ball

3. What is a trailer ball?

A trailer ball is the immediate connection point between your vehicle and trailer. It is made up of a metal ball and a threaded shank or stem. Connected to the trailer coupler, a trailer ball allows you to turn corners and travel smoothly over bumps and hills.

Trailer balls come in a few standard sizes. This makes things easier when finding the right fit for your trailer coupler.

What Is a Trailer Ball - DiagramWhat Is a Trailer Ball - Diagram
What Is a Hitch BallWhat Is a Hitch Ball

What is a hitch ball?

A hitch ball is another name for a trailer ball. Because it mounts onto the trailer hitch and provides the immediate coupling point for the trailer, a trailer ball can rightly be called a hitch ball.

Most hitch balls -- or trailer balls -- come with a nut and washer that allow them to be fastened to a ball mount or trailer hitch tongue. Others are made to be welded into place.

Towing Tip!

Trailer balls require an high amount of torque for installation -- some far beyond your average torque wrench. You can take it into an automotive shop or buy a ball mount with a trailer ball already installed.

What Is a Hitch PinWhat Is a Hitch Pin

4. What is a hitch pin?

A hitch pin is a small metal rod that keeps a ball mount shank and other trailer hitch parts from sliding out of a hitch receiver tube. Typically, a hitch pin is bent in an "L" shape. It is designed to insert into the side of the hitch receiver, pass through the ball mount shank and come out the other side.

Hitch pins also have a hole on the end to accept a hairpin-shaped clip. The hitch clip is made from spring steel and keeps the pin retained in the receiver.

What Is a Hitch Pin - DiagramWhat Is a Hitch Pin - Diagram
What Is a Hitch LockWhat Is a Hitch Lock

What is a hitch lock?

A hitch lock is a key-operated hitch pin that adds security and reassurance to your trailer hitch connection.

Like a hitch pin, a hitch lock inserts into the side of the receiver tube and passes through the ball mount or other hitch accessory. Instead of a clip, however, a hitch lock is equipped with a key-operated padlock or cap. This helps deter theft of your trailer, particularly when left unattended.

Learn more about how to select a lock.

What Is a Trailer CouplerWhat Is a Trailer Coupler

5. What is a trailer coupler?

A trailer coupler, in conjunction with a trailer ball, connects a trailer to your vehicle. What is the front part of a trailer called? The answer is a trailer coupler. It is designed to latch onto a trailer ball and articulate around it for smooth towing.

Trailer couplers come in standard sizes, and many can be adjusted for a more secure connection. The size of the trailer coupler must match the size of the trailer ball to operate safely.

What Is a Trailer Coupler - DiagramWhat Is a Trailer Coupler - Diagram

QuickPin No-Latch CouplerQuickPin No-Latch Coupler

Stress-free, No-latch Coupling

If you've ever coupled a trailer, you know how stubborn a coupler latch can be.

That's why QuickPin™ does away with the traditional latch design. In fact, it doesn't have a latch at all! Hook up your trailer with a simple, single pin, and leave the stress behind.

See how it works

What Is a Safety ChainWhat Is a Safety Chain

6. What is a safety chain?

A safety chain is a length of chain strong enough to keep the trailer from completely separating from the vehicle if it ever becomes disconnected while towing. Two safety chains should be used on every towing setup.

Safety chains are fixed to the trailer tongue and have hooks that allow them to be linked to a vehicle's trailer hitch.

What Is a Safety Chain - DiagramWhat Is a Safety Chain - Diagram

What Is a Trailer Wiring HarnessWhat Is a Trailer Wiring Harness

7. What is a trailer wiring harness?

A trailer wiring harness is a length of wire at the back of a vehicle that allows its electrical system to connect to a trailer. Integrated with the vehicle's existing wiring, it provides a standard connector, such as a 4-way flat plug.

A trailer wiring harness is one of the most vital towing parts but can often be overlooked. It supplies power to the trailer lights and synchronizes them with the vehicle's taillights. It can also be used to connect trailer brakes and auxiliary power.

What Is a Trailer Wiring Harness - DiagramWhat Is a Trailer Wiring Harness - Diagram

What Is a Tow VehicleWhat Is a Tow Vehicle

8. What is a tow vehicle?

A tow vehicle is any car, truck, van, crossover, SUV, RV or other automotive vehicle -- even an ATV -- used to pull a trailer.

Different tow vehicles have different weight capacities. As a rule, the lowest-rated towing component -- including the tow vehicle! -- must always limit the maximum amount of weight you can tow.

What's my towing capacity?

What Is a Tow Vehicle - DiagramWhat Is a Tow Vehicle - Diagram

What Is a TrailerWhat Is a Trailer

9. What is a trailer?

A trailer is any wheeled construction that is pulled by another vehicle. Some common trailer types include utility trailers, popup campers, travel trailers, livestock trailers, flatbed trailers and boat trailers. A trailer can also be an automotive vehicle when it is dinghy towed by an RV.

Just like vehicles, trailers range in weight capacity.

What does my trailer weigh?

What Is a Trailer - DiagramWhat Is a Trailer - Diagram
Flatbed Trailer Landscaping Lawn Tractor TruckFlatbed Trailer Landscaping Lawn Tractor Truck

What equipment is required to be on a trailer?

A standard trailer must have working trailer lights, two safety chains and a properly rated trailer coupler. Larger trailers weighing 3,000 pounds or more must also have trailer brakes.

Safety is the highest priority. To safely tow your trailer, you may also need some additional towing equipment, such as ratchet straps to tie down cargo.

For questions about trailer license plates and local regulations, we recommend consulting the Department of Transportation.

Not sure where to begin? Look up your vehicle to find a custom hitch!

Towing 101 Table of Contents

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