Torque Spec Rating for Curt Rota-Flex Skit Plate Bolts

Updated 03/17/2023 | Published 03/16/2023

Question:

For the rota-flex pin box, I can find online bolt tightening instructions for the bolts that mount from the pin box to the frame. My issue is when I got home from buying a Cougar 32BH 5TH wheel that has a rota flex pin box installed on it, the two bolts that hold the king pin plate to the pin box part were falling out and were almost lost going down the highway. I tightened them up as tight as I could go but are there any instructions to tell you how tight they need to be.

asked by: James B

Expert Reply:

Oh wow, that's definitely not a good experience but I'm glad you made it home safely!

The bolts that hold the rotating skid plate to the Rota-Flex pin box, like part # LC328329, are definitely Grade 5 bolts and although I'm unsure which exact size they are, Curt/Lippert does give us a torque spec guide in the Rota-Flex instructions so you just have to confirm the size of the bolt and make sure the torque spec matches:

1/2"-13 is 65 ft-lbs
5/8"-11 is 135 ft-lbs
3/4"-10 is 220 ft-lbs

Please note that it's okay to be able to rotate that plate by hand. As long as the torque spec is met, that's the most important part.

It's also a good idea to check the torque on all of the bolts periodically - not only for the pin box but also your 5th wheel hitch just to make sure everything is in good working order.

expert reply by: Jon G