Towing Setup & Capacity
Trailer Hitch Receiver Sizes
Four openings, two pin diameters, and one adapter you should probably not buy. Measure the inside of the tube, not the outside.
By Mike M. ·
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Quick picks
What fits a 2 in receiver, which is what most trucks and SUVs have.
| # | Product | Best for | Score | Price |
|---|---|---|---|---|
| 1 |  Andersen Rapid Hitch Adjustable Ball Mount, 3410 Aluminum body, plate-steel dual ball, six inches of drop or rise. The practical case for it is owning two trailers with different coupler heights and one ball mount. | One mount that fits a trailer and a utility trailer | 7.7/ 10 | |
| 2 |  CURT Barbell Hitch Lock, 5/8 in, 23518 A 5/8 in locking pin for a 2 in receiver. Cheap, and it stops the single most casual theft on the list: somebody pulling the clip and walking off with your ball mount. | Replacing the pin and clip on a ball mount you leave in | 6.8/ 10 | |
| 3 |  CURT Chrome Trailer Hitch Ball, 2-5/16 in, 10,000 lb, 40007 A 2-5/16 in ball on a 1 in shank rated to 10,000 lb. If your coupler says 2-5/16, no other size is acceptable, and this is the plain correct answer. | The ball most travel trailers over 5,000 lb actually need | 8.9/ 10 | |
| 4 |  GEN-Y Mega-Duty 12.5 in Drop Hitch Ball Mount Twelve and a half inches of drop at a 10,000 lb rating, built in the USA. This is the category where a budget mount is genuinely the wrong answer. | A lifted truck that needs real drop with real capacity | 7.7/ 10 |
Tap any row to jump to the full write-up. Prices come from Amazon and are read automatically — see each product below for the date.
The short answer
The chart
| Opening (inside) | Pin diameter | Classes | Where you see it |
|---|---|---|---|
| 1-1/4 in | 1/2 in | Class 1, Class 2 | Cars, crossovers, small SUVs |
| 2 in | 5/8 in | Class 3, Class 4, most Class 5 | Trucks, full-size SUVs |
| 2-1/2 in | 5/8 in | Heavy Class 5 | Heavy-duty trucks |
| 3 in | 5/8 in or larger | Commercial | Medium-duty and commercial trucks |
Measure the inside of the tube, flat side to flat side. Measuring the outside gives you a number about a quarter inch bigger and sends you looking for a size that does not exist.
Pin diameter: the ordering mistake
Two sizes, not interchangeable:
- 1/2 in pin for a 1-1/4 in receiver
- 5/8 in pin for a 2 in receiver and up
A 1/2 in pin in a 2 in receiver will go in and will rattle, because it does not fill the hole. The play wears the hole oval over time. If you are not sure which you need, a combo lock set that includes both covers you — the lock picks flag which is which.
Pin length matters too. A standard pin suits a single ball mount; a longer pin is needed if you are also securing a reducer sleeve or a stacked accessory.
Adapters: the honest assessment
Two kinds exist, and they are not equally sensible.
Step-up adapters (1-1/4 in to 2 in). These let a 2 in accessory go into a 1-1/4 in receiver. The limiting rating remains that of the 1-1/4 in receiver, and the adapter extends the lever arm, which increases the bending moment for the same load. Fine for a bike rack rated well within the receiver’s capacity. Not a route to towing a travel trailer.
Step-down sleeves (2-1/2 in to 2 in). These let a standard 2 in mount go into a heavy 2-1/2 in receiver. More reasonable, because the receiver is stronger than the accessory, and many heavy-duty trucks ship with one. Use the sleeve the vehicle or receiver maker supplies if there is one.
The common mistake
The rattle, and how to stop it
Every receiver has clearance between the tube and the mount, and that clearance rattles. It is irritating and it is also wear: the mount moving in the tube pounds the hole and the pin.
Three fixes, cheapest first. A wedge-style anti-rattle device clamps the mount against one wall of the tube. A threaded anti-rattle pin replaces the standard pin with one that tightens. Or a shim — a bolt-on plate that takes up the slack. All three work; the threaded pin is the neatest because it is also the lock.
One note for weight distribution
A weight distribution hitch does not use a ball mount. The head bolts to a dedicated weight distribution shank, which slides into the receiver like a ball mount but has a specific hole pattern on its upright to carry the head.
So if you need drop for a lifted truck with weight distribution, you need a high-drop WD shank rather than a drop ball mount, and the shank must match your head’s hole pattern. The lifted-truck page covers this.
What to remember
- Measure the inside of the receiver tube, flat side to flat side.
- 1-1/4 in receivers take a 1/2 in pin; 2 in and up take 5/8 in.
- A step-up adapter does not raise the smaller receiver's rating and adds leverage.
- Never stack extensions and drop adapters.
- An anti-rattle pin fixes the noise and locks the mount at the same time.
The picks in full
Andersen Rapid Hitch Adjustable Ball Mount, 3410
Andersen Hitches · Best for one mount that fits a trailer and a utility trailer
Aluminum body, plate-steel dual ball, six inches of drop or rise. The practical case for it is owning two trailers with different coupler heights and one ball mount.
Key specifications
- Drop / rise
- 6 in
- Balls
- 2 in and 2-5/16 in plate steel dual ball
- Receiver
- 2 in
- Body
- Aluminum
Capacity figures read from Andersen Rapid Hitch specifications, October 2026.
How it scored
- Rated capacity (25%)8
- Adjustability (25%)9
- Security (20%)6
- Build quality (15%)8
- Price for capability (15%)7
Weighted average of the figures above. We did not test this product — see how we pick.
What it does well
- Flip the ball plate instead of buying a second mount
- Aluminum means you can actually lift it
- Generous drop and rise range
What it is bad at
- Aluminum galls against a steel receiver if you never grease it
- The pin and clip are the weak point for theft unless you add a lock
- Costs as much as three fixed mounts
Price as of October 5, 2026. #ad How this is funded
CURT Barbell Hitch Lock, 5/8 in, 23518
CURT · Best for replacing the pin and clip on a ball mount you leave in
A 5/8 in locking pin for a 2 in receiver. Cheap, and it stops the single most casual theft on the list: somebody pulling the clip and walking off with your ball mount.
Key specifications
- Pin diameter
- 5/8 in
- Fits
- 2 in receivers
- Type
- Barbell style
- Finish
- Black
Capacity figures read from CURT hitch lock specifications, October 2026.
How it scored
- Security (35%)6
- Fit range (25%)7
- Weather resistance (20%)5
- Everyday usability (10%)9
- Price for capability (10%)10
Weighted average of the figures above. We did not test this product — see how we pick.
What it does well
- The cheapest security upgrade on the whole site
- Barbell shape is harder to lever than a padlock-style pin
- Fits the 2 in receiver on most half-ton trucks
What it is bad at
- 5/8 in only — a 1-1/4 in receiver needs a 1/2 in pin
- The lock cylinder is the first thing to corrode
- Protects the mount, not the trailer
Price as of October 5, 2026. #ad How this is funded
CURT Chrome Trailer Hitch Ball, 2-5/16 in, 10,000 lb, 40007
CURT · Best for the ball most travel trailers over 5,000 lb actually need
A 2-5/16 in ball on a 1 in shank rated to 10,000 lb. If your coupler says 2-5/16, no other size is acceptable, and this is the plain correct answer.
Key specifications
- Ball diameter
- 2-5/16 in
- Capacity
- 10,000 lb
- Shank
- 1 in diameter x 2-1/4 in long
- Finish
- Chrome
Capacity figures read from CURT hitch ball specifications, October 2026.
How it scored
- How often you use it (40%)9
- Build quality (25%)8
- Takes up little room (20%)9
- Price for capability (15%)10
Weighted average of the figures above. We did not test this product — see how we pick.
What it does well
- Correct size for the majority of mid-size and larger travel trailers
- Cheap enough to keep a spare
- Chrome finish resists the rust that seizes a coupler
What it is bad at
- A 1 in shank will not fit a ball mount drilled for 3/4 in
- Chrome chips, and then it rusts under the chip
- Needs a torque wrench to tighten properly, which most people skip
Price as of October 5, 2026. #ad How this is funded
GEN-Y Mega-Duty 12.5 in Drop Hitch Ball Mount
GEN-Y Hitch · Best for a lifted truck that needs real drop with real capacity
Twelve and a half inches of drop at a 10,000 lb rating, built in the USA. This is the category where a budget mount is genuinely the wrong answer.
Key specifications
- Drop
- 12.5 in
- Capacity
- 10,000 lb
- Receiver
- 2 in
- Origin
- Made in USA
How it scored
- Rated capacity (25%)9
- Adjustability (25%)7
- Security (20%)7
- Build quality (15%)9
- Price for capability (15%)6
Weighted average of the figures above. We did not test this product — see how we pick.
What it does well
- Enough drop for a genuinely lifted truck without stacking adapters
- Capacity holds up at full drop, which is the spec that usually collapses
- Heavy-gauge construction
What it is bad at
- Very heavy to handle and store
- Expensive
- Overkill for a stock-height truck
Price as of October 5, 2026. #ad How this is funded
Common questions
Measure the inside of the tube, flat side to flat side. Common sizes are 1-1/4 in and 2 in, with 2-1/2 in and 3 in on heavy-duty and commercial vehicles.
5/8 in. A 1-1/4 in receiver takes 1/2 in. Using the smaller pin in the larger receiver leaves play that rattles and wears the hole oval.
A wedge clamp, a threaded anti-rattle pin, or a bolt-on shim. The threaded locking pin is neatest because it also secures the mount against theft.
Sources
- SAE J2807 — tow-vehicle gross combination weight rating procedure — read October 2026
- SAE J684 — trailer couplings, hitches and safety chains — read October 2026
- 49 CFR 393.70 — coupling devices and towing methods — read October 2026
- CURT published towing product specifications — read October 2026