Ball Mount and Trailer Ball
The clearest CURT overview for matching ball diameter to the coupler and shank size to the ball mount hole.
Watch on YouTube →Trailer Ball Size Guide (Canada)
Picking a trailer ball in Canada should feel simple. Measure the coupler on the trailer, then match that diameter — one and seven eighths, two inch, or two and five sixteenths. The ball is not the hitch and it is not the ball mount. Get those three pieces talking to each other and the trailer sits happier on the highway.
Built for Canadian shoppers. Free shipping on CURT towing gear from Lots of Parts when the SKU is live on this store.
Pair this page with the
ball mount guide,
how to measure ball mount drop, and
tongue weight explained.
Prefer the full index?
Open the towing guides hub.
Watch these CURT videos first
All four videos are from the official CURT YouTube channel (@curtmfg). Start with ball mount and trailer ball selection, then use hitch class and wiring basics if you are still building the rest of the setup.
If an embed does not load, use the YouTube link under the card.
How to Select a Trailer Hitch
Ball size sits downstream of hitch class and receiver size. Get the tube right before you obsess over chrome.
Watch on YouTube →CURT Install Techniques
Torque habits matter on the hitch first. The ball nut still needs a proper wrench pass after you pick the diameter.
Watch on YouTube →Trailer Wiring Harness Basics
Lights and brakes are a separate shopping lane from ball diameter. Do not let a shiny ball distract you from a dark trailer.
Watch on YouTube →The three common ball diameters
Walk up to the trailer coupler with a tape or a stamped size on the latch housing. You are looking for one of three everyday diameters on Canadian light and medium trailers.
Small coupler
One and seven eighths
Common on lighter utility trailers and some lawn or ATV gear. Coupler and ball must both say one and seven eighths. A two inch ball will not seat correctly here.
Most common
Two inch
The everyday size for many boat, utility, and camping trailers in Canada. If the coupler stamp says two inch, buy a two inch ball — not “close enough.”
Heavy trailer
Two and five sixteenths
Larger gooseneck-adjacent light trailers and heavier bumper-pulls often use this diameter. It will not lock into a two inch coupler. Measure twice.
Also check
Shank size and rise
The ball has a shank that must fit the hole in your ball mount. Common shanks are three quarter inch, one inch, and one and one quarter inch. Rise on some balls changes how the coupler sits.
How the parts stack
Receiver hitch on the vehicle. Ball mount slides into that receiver. Trailer ball bolts through the ball mount. Coupler on the trailer clamps onto the ball. Tongue weight presses down through that stack — which is why the tongue weight guide belongs in the same shopping trip as ball diameter.
Drop or rise lives on the ball mount, not on the ball itself. Use the measure drop guide so the trailer sits level. The ball mount guide covers shank length and class ratings in more depth.
| Ball diameter | What it usually pairs with |
|---|---|
| One and seven eighths | Light utility and small recreational trailers with a matching coupler stamp. CURT examples linked below include 40015, 40016, and 40017. |
| Two inch | Everyday Canadian trailers with a two inch coupler. CURT examples linked below include 40003, 40004, 40018, 40053, 40066, and 40090. |
| Two and five sixteenths | Heavier couplers that call for the larger ball. CURT examples linked below include 40005, 40006, 40009, 40035, 40086, 40088, and 40178. |
Shop live CURT balls by size
These SKUs are active on Lots of Parts today. Read each card for shank diameter, capacity, and finish. Free shipping applies on CURT gear from this store when the SKU is live. Capacities on the ball never override the lowest rating in your hitch, mount, vehicle, or trailer chain.
One and seven eighths inch balls
In stock
CURT 40015
One and seven eighths ball, three quarter inch by two and one eighths shank, chrome, rated to two thousand pounds on the card.
In stock
CURT 40016
One and seven eighths ball, three quarter inch by three inch shank, chrome, rated to two thousand pounds on the card.
In stock
CURT 40017
One and seven eighths ball, one inch by three inch shank, chrome, rated to three thousand five hundred pounds on the card.
Two inch balls
In stock
CURT 40003
Two inch chrome ball with a three quarter inch shank, rated to three thousand five hundred pounds on the card.
In stock
CURT 40004
Two inch chrome ball with a one inch shank, rated to six thousand pounds on the card. Strong everyday stock.
In stock
CURT 40018
Two inch chrome ball with a three quarter inch shank, rated to three thousand five hundred pounds on the card.
In stock
CURT 40066
Two inch chrome ball with a one inch shank, packaged, rated to six thousand pounds on the card.
In stock
CURT 40053
Two inch stainless ball, one inch by two and one eighths shank, rated to six thousand pounds on the card.
In stock
CURT 40090
Two inch coupler fit with a one and one quarter inch shank path on the card — read the product page for capacity and rise notes.
Two and five sixteenths inch balls
In stock
CURT 40005
Two and five sixteenths chrome ball with a one inch shank, rated to seven thousand five hundred pounds on the card.
In stock
CURT 40006
Two and five sixteenths chrome ball with a one and one quarter inch shank, rated to ten thousand pounds on the card.
In stock
CURT 40035
Two and five sixteenths chrome ball with rise on a one and one quarter inch shank path, rated to ten thousand pounds on the card.
In stock
CURT 40009
Two and five sixteenths chrome ball, one and one quarter by two and three quarter inch shank, heavy rating on the card.
In stock
CURT 40178
Two and five sixteenths chrome ball, packaged, one and one quarter by two and five eighths shank path on the card.
In stock
CURT 40086
Two and five sixteenths raw steel ball for heavy couplers — read shank and capacity notes on the product card.
In stock
CURT 40088
Two and five sixteenths raw steel ball with a large shank path for heavy duty mounts — confirm fitment on the card.
Parts-counter tips that prevent comebacks
Coupler first
Stamp beats memory
If the coupler is painted over, clean the stamp or measure the mouth. Guessing between two inch and two and five sixteenths is how balls get returned.
Shank second
Hole size on the mount
A correct diameter ball with the wrong shank will not torque into your mount. Bring the mount or its hole size when you shop.
Ratings
Lowest number wins
Ball capacity, mount capacity, hitch class, vehicle tongue limit, and trailer rating — the lowest honest number is the one you live with.
Level ride
Drop is separate
Ball diameter does not set trailer attitude. Measure drop on the mount so the coupler sits level once the ball is locked.
Step 1Read the coupler
One and seven eighths, two inch, or two and five sixteenths — write it down.
Step 2Check the mount hole
Match shank diameter and length to the ball mount you actually own.
Step 3Respect tongue weight
Use the tongue weight guide so the stack is not overloaded even with a strong ball.
Step 4Set drop and torque
Level the trailer, then torque the ball nut to the instruction sheet.
Related guides we do publish
Ball mount guideDrop, rise, and class pairing
Measure dropLevel trailer attitude
Tongue weight explainedDownforce through the ball
What hitch classReceiver context first
Towing guides hubAll vehicle and topic guides
Shop a common two inch ball
CURT 40004 is a live two inch chrome ball with strong stock when your coupler stamp says two inch. Free shipping on CURT gear from Lots of Parts.
Open CURT 40004 →Still choosing a mount? Open the ball mount guide. Need drop numbers? Use how to measure ball mount drop.
Lots of Parts · Canada trailer ball size help that spells out one and seven eighths, two inch, and two and five sixteenths in plain English, links live CURT SKUs, and points you to ball mount, drop, and tongue weight guides. No fake reviews, no price games.
