What Pin Box Does The Curt Helix C63RJ Replace?

Updated 01/14/2025 | Published 01/13/2025

Question:

Does the Curt Helux C63RJ fit in the Lippert 1621 pin box mount? Is this pin box the same length as the 1621 pin box? I have a 2020 Grand Design Reflection 311BHS and I want to keep the same clearances with an upgraded pin box.

asked by: Ted J

Expert Reply:

Hey Ted. The Curt Helix Pin Box # C63RJ replaces the Lippert Rhino box pin box. So it will not replace your 1621 pin box. I checked with my contact at Curt and they said they are only doing the Rhino box for now, but they hope to add other bolt patterns later down the line.

There would be no length difference between your 1621 pin box and the Curt Helix. Most any aftermarket pin box will be the same length.

If you are looking for an upgraded, shock-absorbing pin box to replace your 1621, take a look at the Gen-Y # 325-GH-8040. These pin boxes use torsion rubber to absorb shock, and they do work very well. This model replaces the 1621 and is correct for your 13,995 lb GVWR. Definitely a solid alternative to the Curt, plus the Gen-Y is available now, while the Curt is pre-order still.

expert reply by: Jesse M

Ted

1/14/2025

Thanks for that info, it isn't what I was hoping to here. I am considering the GenY model you mentioned but I read that it is 2 inches shorter in length and worry that it will change the clearance I have to the cab corners of my truck when turning.

Jesse M.

1/14/2025

@Ted The # 325-GH-8040 I mentioned measures 16.33" from the center of the pin to the first row of bolt holes so yes it is slightly shorter than the stock 1621 pin box. If you follow the link below it will show you a question page with more detailed dimensions if you want to compare.

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