Best Hitch Ball and Hitch Lock for Trucks (CURT set)

For you if: the truck has a 2″ square receiver and you tow with a 2″ coupler on a conventional ball mount; you need a matched chrome 2″ ball plus a keyed lock pin so the mount does not walk off the tube in a parking lot; and you will size the ball to the lower of trailer GTW need and every other rating in the system.

Skip this page if: the coupler is 2-5/16″ (gooseneck / many fifth-wheel paths) — wrong ball diameter. Skip if the receiver is 1-1/4″ — wrong lock pin class (need a 1/2″ pin family, not 23515). Skip if you wanted a weight-distribution hitch, a gooseneck ball in the bed, or a fifth-wheel head — those are different pages. Skip 40070 if your entire stack already caps under 6,000 lb and you only need the value ball. Skip 40066 if the trailer rating or your plan needs the 7,500 lb ball line and the rest of the stack can take it.

A hitch ball is the steel sphere your trailer coupler clamps onto. A hitch lock is a keyed pin that replaces a plain hitch pin and clip so the ball mount cannot be pulled out of the receiver without the key. This page covers one brand — CURT — and three part numbers: 40070, 40066, and 23515. You pick one ball for the coupler you actually have, then add the lock for the 2″ receiver you actually have.

Both 40070 and 40066 are 2″ balls for 2″ couplers. A 1-7/8″ coupler and a 2-5/16″ coupler are different hardware. Gooseneck and many fifth-wheel setups use a different ball or kingpin path entirely — not these SKUs. If the latch on the coupler does not close cleanly on a 2″ ball, stop and fix the mismatch before you tow.

CURT prints 7,500 lb GTW on 40070 and 6,000 lb GTW on 40066. Those are ball capacities. Your legal and safe tow limit is still the lowest number among the truck’s tow rating, the hitch receiver rating, the ball mount rating, the ball, the coupler, and the trailer GVWR / GTW. CURT’s own ball copy repeats the same rule: never exceed the lowest weight capacity of any towing component. Plan the haul around that floor, not around the highest stamp on the ball.

40070 and 40066 share the practical form factor truck owners care about for a common class 3 / class 4 ball mount: 2″ ball, 1″ shank diameter, 2-1/8″ shank length, chrome finish, fine threads, nut and lock washer. The published split is capacity — 7,500 vs 6,000 lb GTW. Buy the higher ball when the rest of the stack and the trailer need that headroom. Buy the value ball when 6,000 lb already clears your trailer and every other rating. Do not buy 40070 thinking it upgrades a weaker hitch.

23515 is a 5/8″ pin for a 2″ × 2″ receiver tube. That is the common class 3 / class 4 / many class 5 truck receiver pin size. A 1-1/4″ receiver uses a smaller pin class — 23515 will not fit. A 2-1/2″ or 3″ commercial receiver may use a different pin diameter or a different CURT lock SKU. Measure the hole in the side of the receiver before you order. The lock holds the ball mount (or hitch-mounted accessory) in the tube; it does not replace a coupler lock on the trailer tongue. The Amazon listing wired here is a pack of 2.

Weight-distribution hitches spring-bar the tongue load across the truck and trailer. Gooseneck balls mount in the bed over the rear axle. Fifth-wheel heads latch a kingpin in the bed. None of those jobs are 40070, 40066, or 23515. If search sent you here for a Turnoverball, a slider fifth-wheel, or a WDH head, leave this page and use the hitch-system guides.

Ball mount first. Confirm the ball-mount hole is for a 1″ shank and that the platform is at least 3/8″ thick. CURT’s note on both ball pages: the hole must not be more than 1/16″ larger in diameter than the threaded shank. Drop the shank through, seat the lock washer and hex nut, and torque to the mount maker’s spec (CURT prints 250 ft-lb torque on the 40066 spec block; follow the ball-mount and ball instructions you have in hand). Recheck the nut after the first loaded miles.

Coupler match. Latch a 2″ coupler onto the 2″ ball and confirm full closure and safety-pin / latch lock before you roll. Do not force a 2-5/16″ coupler onto these balls.

Receiver lock. Slide the ball mount into the 2″ receiver, align the side holes, push 23515 through, and turn the key 1/4 turn to lock. Cap the keyway with the watertight dust cap so grit and wash water stay out of the mechanism. Keep the spare key off the truck keyring you leave with a valet. Amazon quantity for this guide: pack of 2.

Capacity floor. Write down truck tow rating, hitch rating, ball-mount rating, ball GTW (7,500 or 6,000), coupler rating, and trailer rating. Tow to the lowest number. The hitch lock does not change that math.

Wrong sizes to avoid. Do not order 23515 for a 1-1/4″ receiver. Do not order 40070 / 40066 for a gooseneck coupler. Do not treat a stainless CURT lock SKU or a right-angle lock SKU as 23515 without reading the part number on the maker page or the Amazon title.

Wipe road salt off chrome balls and the lock after winter miles so the finish lasts the one-year finish window CURT prints. Seat the dust cap on 23515 every time you lock it. Recheck the ball nut and lock washer after the first hard haul and after any curb strike on the mount. Replace a ball that shows cracked plating into raw pits, egg-shaped wear under the coupler, or damaged threads. Replace a lock that will not turn cleanly or that has a seized dust cap — do not hammer a stuck key.

Prices change — check the live listing when you buy.