CURT Helux fifth-wheel pin boxes use a coil spring and shock to help moderate towing chucking and road shock. The seven fifth-wheel models in this range look similar, but their suspension springs are selected for different loaded pin weights. Choose from the chart—not just a trailer's advertised gross weight.

18,000 lb trailer-capacity group

Models 2024044568, 2024044567 and 2024044569 are the 18K fifth-wheel variants, with different optimal pin-weight ranges.

24,000 lb trailer-capacity group

Models 2024122233, 2024044570, 2024044571 and 2024044572 are in the 24K range. The higher capacity does not mean the spring suits every pin weight.

Match loaded pin weight to the correct Helux

CURT MPN Optimal loaded pin weight Spring rating Trailer capacity
2024044568 1,880–2,377 lb 1,100 lb 18,000 lb
2024044567 2,378–2,722 lb 1,250 lb 18,000 lb
2024044569 2,723–3,165 lb 1,500 lb 18,000 lb
2024122233 3,166–3,712 lb 1,500 lb 24,000 lb
2024044570 3,713–4,332 lb 1,800 lb 24,000 lb
2024044571 4,333–4,900 lb 2,000 lb 24,000 lb
2024044572 4,901–6,000 lb 2,300 lb 24,000 lb

Optimal loaded pin-weight ranges are CURT's selection guidance. The spring rating is a separate specification, not the same as the trailer's pin weight or gross trailer rating.

How to choose the appropriate model

  1. Measure loaded pin weight. CURT recommends weighing the fifth wheel in travel-ready condition at a certified scale. Pin-weight estimates based on GVWR can be inaccurate.
  2. Find the optimal range. Compare the measured pin weight to the chart above. Do not select solely on the 18K or 24K gross trailer capacity.
  3. Check the mounting pattern. This fifth-wheel Helux family uses the Rhino Box bolt-mounting pattern; verify the trailer's existing pin-box mount and required clearance.
  4. Check the hitch. The fifth-wheel models have a standard kingpin connection, not a gooseneck-ball coupler. CURT lists an exclusion for offset fifth-wheel hitches.
  5. Plan a safe installation. Follow the exact CURT installation manual, use the new mounting hardware specified for the kit and support the heavy pin box with sufficient people or suitable lifting equipment.
Capacity and fit: The vehicle, hitch, pin box, RV frame and suspension must all be suitable for the towing arrangement. Do not exceed the lowest applicable rated component. A model with a higher maximum capacity is not automatically a better spring match.

Seven fifth-wheel Helux pin boxes in our catalog

Open the exact MPN for the item details and online availability.

Our CURT Helux gooseneck comparison covers a different family that attaches to a gooseneck hitch ball rather than a conventional fifth-wheel hitch.

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