Choosing Your Trailer Hitch Ball Size – A Step By Step Guide

Last Updated on January 8, 2023 by Will Sabel

Ever caught yourself buying the trailer ball for the third time and it still doesn’t fit? 

I know — we all have been there.

While towing, itself, can be confusing at times, imagine the confusion that a newbie has to go through to choose a decent trailer ball.

Keeping all of us in remembrance, let’s talk about the whole concept of hitch ball today. Before I jump into the steps, we’ll start with the basics of ball mount and trailer balls.

I’m including some of the staple-hitch-knowledge for better understanding. Yes, I’m quoting it from the internet because I’m not too big on theories.

Towing usually has three parts; the trailer, the medium used for the connection, and the truck or the carrying vehicle. Parts like trailer hitch, trailer all, etc are popularly known for their usability and utility. 

What is a Ball Mount?

Ball Mount

In simple words for beginners, a ball mount is an accessory to the receiver’s hitch. 

The body includes a trailer ball platform and a shank. The platform provides the mounting point for the trailer. The shank you get, inserts itself into the hitch receiver tube.

It is a removable hitch that fastens the receiver of the hitch with a clip and pin. It is easily used to drop or raise the trailer or vehicle for level towing.

Every ball mount comes in both fixed and adjustable positions. So don’t sweat it.

You’ll notice that ball mounts come with a hole in their shank to accept hitch lock or hitch pin. Some exclusions include trailer balls being pre-torqued or combined into places. 

These are known as ‘loaded’ ball mounts. 

Not all mounts fit the same receiver tubes. Here’s a list of all mounts and the receiver tubes that it is supposed to fit: 

  • Class I & II: 1-1/4″ receiver tube
  • Class III & IV: 2″ receiver tube
  • Class V: 2″ or 2-1/2″ receiver tube

A ball hitch is another name for ball mount and like the previous one, acts as a receiver accessory. This acts as a medium to connect with the trailer. 

Despite that, I’m attaching a brief discussion on what a ball hitch is below.

What is a Ball Hitch?

A hitch ball or ball hitch (also called a trailer ball or just ball) is the ball-shaped extension that connects the trailer to a hitch and holds the towing process together. 

The diameters of the hitch ball are very similar if not identical. But the hitch ball weight ratings and shank diameters may differ from one another. 

The rating of the hitch ball is equally substantial as the receiver hitch ratings.

Let me guide you through different parts/concepts of the ball hitch in this section of my piece.

What is Ball Diameter Exactly? 

It’s the total diameter of the ball head that is situated on the top of the structure. 

You can check the top of the trailer coupler for the size of ball diameter. You will find sizes stamped on the body. 

Recreational and light commercial hitch balls come in different sizes. Those sizes can include 1-7/8″, 2″, 2-5/16″, and occasionally 3″.

If you ask me, it’s an easy calculation. Lighter trailers will use smaller hitch balls and vice versa. 

Nevertheless, the size match is extremely necessary for the correct hitch ball and perfect size ball.

What do I Mean by a Shank Diameter? 

Shank diameters can be found in a variety of sizes (5/8″, 3/4″, 1″, and 1-1/4″ for example) and capacities (7,000lbs to 17,000lbs). 

Generally, the diameter of the threaded shaft put into the trailer through the ball mount is the shank diameter

Explaining Shank Length for My Readers

Shank length is the middle length between shank diameter up to shank rise. In other words, this is the length of the shaft that spreads crossing the mounting base of the hitch ball. 

It is necessary to use a shank that is big and long enough to stretch exceeding the thickness of the drawbar mounting tab. This is to make sure that enough threads are obtainable to fasten the ball to the mount.

What is Shank Rise? 

The altitude of the shank can be used to raise a trailer back to level. This has a role in the ‘drop’ or ‘rise’ part of the shank and towing procedure. 

Towing With Too Much Rise
Towing With Too Much Drop
Level Towing

Image Source: CURT

How to Choose the Size of Your Trailer Ball?

You’ll find several available sizes of trailer hitches if you just take a look at your local shop (or online retail stores). 

Though the variety might intrigue you to try and buy different-sized trailer balls to experiment with, that might not always be a nice option.

But don’t let these shapes and sizes confuse you. I have looked into most of these things and ended up writing a complete guide to help you choose the perfect trailer ball that your truck needs.

Before we start, ask yourself this:

  • How much weight do you need to tow?
  • How much drop or rise do you need?
  • Size of the receiver tube the trailer hitch has.

After you have decided all your requirements, it’s all easy steps. All you need to do is go through the below steps and find your perfect match!

Hitch ball size chart
Image Credit: Weigh-Safe

Factors to Consider While Opting for One of These Babies

There are some factors that you need to consider to choose the perfect-sized ball mount. I’ve spent hours researching these things. Quite a lot came up on my plate and I had to get some sorting done. I had to do quite a bit of measurement on my own as well.

Measure the Rise and Drop You Have

You will need to see how much drop or rise is needed for a safe and level towing setup. 

For this, you have to calculate the receiver height measurement. Here are the steps that you will need to follow:

Take the measuring tape and start measuring from the ground to the top inside edge of the receiver tube.

Measure Your Coupler as Well

With that, I’m off to our next measurement. Here, you will need the coupler’s measurement.

But before that, you will have to manually level out the trailer. Make sure it’s well leveled, otherwise it will mess up the coupler’s height.

Now that we are all set, measure from the ground to the bottom of the coupler. 

Run Some Calculations

At this point, you are done taking all the relevant measurements. 

Keep those secured because you are going to do some calculations here.

The final calculation

  • Subtract the receiver height from the coupler height. 
  • If the answer is negative, then it will show you how many drops you need. 
  • If that answer is positive, then that’s the amount of rising your trailer needs. 

Selecting the trailer ball is Vital as Well

Typically, coupler manufacturers will stamp the correct ball size on the body of the coupler itself. 

Even if the size or the measurements do not fit your vehicle, don’t panic. I’m here to solve it. 

Almost all of the couplers are adjustable. You can adjust it to your height or size requirements, this should do the trick. 

To adjust the couple, just tighten or loosen the adjustment nuts. You can find the adjustment nuts underneath the coupler. 

Along with that, keep the shank’s diameter in mind. Just make sure that the shank’s diameter of the trailer ball matches the hole size of the ball mount.

Step 1: Compare the sizes of the ball and Coupler 

When you choose a trailer ball, the first thing you will need to do is to select the ball diameter. Remember to match it to the coupler size. 

Most manufacturers label the mentioned trailer ball size on the coupler’s body. 

Do not forget to ensure a strong connection between your trailer ball and coupler before towing. 

Also, make sure that all the important adjustments have been made before you start your journey.

Step 2: See If the Shank Fits the Trailer Ball Hole or Not

The narrow space in the platform of the bumper hitch is where the trailer ball goes onto. Hence, it is necessary to know the diameter of this hole. 

That way, you can pick a trailer ball that matches your shank’s diameter. 

If the shank size is way too small, it will shift while towing. This will result in them coming loose. 

If the shank size is too spacious, you can use a reducer bushing to make up the difference and that should be it. 

Step 3: Double Check the Weight Capacity 

When you select a trailer ball or towing accessory of any kind, you need to consider the mentioned weight capacity. 

Generally, the weight rating is listed as the ball capacity for the trailer ball. Keep in mind that this will not reflect the tongue weight.

That’s why you should select a trailer ball whose capacity is not limited to the gross weight of your trailer. 

Choosing the perfect-sized ball mount can be an exhausting experience. Hopefully, with this rather simplified guide; this should be an easy read. 

Now you can easily find the perfect match for hitches and trailers. The process may vary for some people and is not limited to this. So, good luck choosing yours!

How to choose trailer hitch ball size

People Also Asked…

Author: Will Sabel

Will Sabel is an avid car enthusiast. When he's not writing for RidersWant, you'll find him cruising the country in a new car. People are always wondering how many cars he has!

Leave a Comment