CURT Helux gooseneck pin boxes replace approved fifth-wheel pin-box connections with a 2-5/16-inch gooseneck ball coupler and a coil-spring/shock-absorber suspension. Six available models share a 20,000-pound gross trailer rating but have different spring and pin-weight ranges. Select by the trailer's measured pin weight and the required pin-box mounting configuration.
Three measurements that determine the right Helux
Measure the vertical weight at the pin/coupler connection using an appropriate scale method. Do not rely solely on an estimated percentage of trailer GVWR.
Account for the cargo and water conditions used in the manufacturer's definition of minimum and maximum weight.
Confirm the original pin-box bolt pattern, trailer structure and 2-5/16-inch towing connection against the current CURT installation instructions.
Helux gooseneck spring and pin-weight comparison
The optimal range is CURT's recommended selection band. The minimum and maximum are operating boundaries under the manufacturer's described load conditions; they are not substitute tow-vehicle ratings.
| Gooseneck MPN | Spring rating | Optimal pin weight | Minimum pin weight | Maximum pin weight |
|---|---|---|---|---|
| 2024044575 | 1,100 lb | 1,650–2,144 lb | 1,350 lb | 2,350 lb |
| 2024044574 | 1,250 lb | 2,145–2,484 lb | 1,550 lb | 2,700 lb |
| 2024044576 | 1,500 lb | 2,485–2,954 lb | 1,800 lb | 3,200 lb |
| 2024044577 | 1,800 lb | 2,955–3,469 lb | 2,200 lb | 3,900 lb |
| 2024044578 | 2,000 lb | 3,470–3,964 lb | 2,450 lb | 4,300 lb |
| 2024044579 | 2,300 lb | 3,965–5,000 lb | 2,800 lb | 5,000 lb |
Minimum: trailer without cargo, with fresh and waste-water tanks empty. Maximum: manufacturer-defined loaded cargo condition. Check the latest model-specific documentation for travel-ready loading and tank requirements.
Trailer compatibility, ball size and towing checks
CURT uses a coil spring and shock absorber to reduce shock and chucking. The gooseneck coupler connects to an appropriate 2-5/16-inch hitch ball. Verify frame and mounting compatibility, safety-chain arrangements and the manufacturer's installation requirements before using a replacement pin box.
These six Helux gooseneck pin boxes are all described with a 20,000-lb gross trailer capacity, but their published spring ratings range from 1,100 to 2,300 lb and their permitted pin-weight ranges differ. Never exceed the lowest-rated trailer, pin box, hitch or tow-vehicle component.
For heavy pin-box installation, support the trailer connection securely and follow CURT's lifting, alignment and torque instructions. Have a qualified installer inspect the assembly if mounting compatibility is unclear.
CURT Helux gooseneck pin boxes by spring choice
Select the appropriate model number below to review product details and availability.
CURT 2024044575
20,000-lb gross trailer rating, 1,100-lb coil spring and 1,650–2,144-lb optimal pin weight.
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CURT 2024044574
20,000-lb gross trailer rating, 1,250-lb coil spring and 2,145–2,484-lb optimal pin weight.
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CURT 2024044576
20,000-lb gross trailer rating, 1,500-lb coil spring and 2,485–2,954-lb optimal pin weight.
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CURT 2024044577
20,000-lb gross trailer rating, 1,800-lb coil spring and 2,955–3,469-lb optimal pin weight.
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CURT 2024044578
20,000-lb gross trailer rating, 2,000-lb coil spring and 3,470–3,964-lb optimal pin weight.
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CURT 2024044579
20,000-lb gross trailer rating, 2,300-lb coil spring and 3,965–5,000-lb optimal pin weight.
View product details and availabilityMore CURT towing component references
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