CURT 2-5/16" Chrome Trailer Hitch Ball 20,000 lb GTW — 1-1/4" x 2-3/4" Shank, Fine Thread

CURT 40008 is a heavy-duty 2-5/16" chrome trailer hitch ball rated for up to 20,000 lbs gross trailer weight, with a 1-1/4" x 2-3/4" shank and supplied hex nut plus lock washer.

This tow ball is built for rugged towing chores where strength, fit, and corrosion resistance matter. Hot-forged, heat-treated steel forms the core of the CURT 40008, finished in chrome to resist weather and road grime. It’s engineered to match standard 2-5/16" couplers and to install securely on properly rated ball mounts or hitch platforms.

How does this hitch ball match my trailer and coupler?

The CURT 40008 has a 2-5/16" ball diameter, the common sizing for many heavy-duty trailer couplers. The ball and shank dimensions ensure proper seating and clearance with compatible couplers and mounts when you confirm platform thickness and hole diameter first.

• Ball diameter: 2-5/16" — fits standard 2-5/16" couplers.
• Shank diameter: 1-1/4" and length: 2-3/4" for ample mounting engagement.
• Zero rise (0") — designed for level towing when used with appropriate mounts.
• Check that your ball mount hole accepts a 1-1/4" shank and platform is at least 3/8" thick.

What towing capacity and safety specs should I expect?

This model carries a 20,000 lb gross trailer weight (GTW) rating when installed correctly and used within the limits of the hitch system. CURT manufactures and tests to meet U.S. VESC guidelines; nevertheless, the lowest-rated component in your towing setup determines safe limits.

• Rated GTW: 20,000 lbs — based on component testing and specification.
• Installation torque: 450 ft-lbs recommended for the hex nut to secure the shank.
• Includes zinc-plated hex nut and helical lock washer for a dependable connection.
• Always verify vehicle, hitch receiver, ball mount, and trailer coupler ratings before towing.

How does the finish and thread type affect durability and holding power?

The CURT 40008 uses a chrome-style plating that sheds moisture and road contaminants to slow corrosion. Fine threads on the shank improve clamp strength between the mount and nut, giving a firmer hold when torqued to specification.

• Finish: nickel-chrome plating for increased resistance to rust and wear.
• Threads: fine thread profile for superior holding after correct tightening.
• Hardware: included zinc-plated nut and helical lock washer resist loosening in service.
• Maintenance: inspect for corrosion or thread wear before long tow runs.

What do I need to check before ordering and installing?

Buying the right hitch ball means confirming coupler size, ball-mount hole diameter, and the required shank length for safe engagement. Proper installation—using the recommended torque and a sufficiently thick mounting platform—ensures the rated capacity can be used safely.

• Confirm coupler accepts a 2-5/16" ball and that your hitch accepts a 1-1/4" shank.
• Platform thickness should be at least 3/8" for mounting strength.
• Use the supplied hex nut and lock washer; torque to 450 ft-lbs as specified.
• Remember the towing system limit is the lowest-rated component’s capacity.

Who is this for: The CURT 40008 is aimed at drivers who tow heavy equipment, large utility trailers, RVs, boats, or agricultural loads and need a robust, standards-compliant 2-5/16" trailer ball. Choose this model if your vehicle, hitch, and trailer setup require a 20,000 lb-rated ball with a 1-1/4" shank, corrosion resistance, and secure hardware for dependable, heavy-duty towing.