Rota-Flex 1621 Compatible Pin Box Fit with Lippert 1621HD Brackets

Question

Question:

Will the 21,000lb rota-flex pin box mount on a sPM qtandard 18,000lb 1621hd frame?

asked by: Chris

0

Expert Reply:

The Trailair Rota-Flex 5th Wheel Pin Box - Lippert 1621 - 21,000 lbs # LC328329 will mount on the standard 18,000 lb 1621HD frame with one hole modification. The actual trailer capacity won't increase, so you may want to stick with the 18K Rota-Flex # LC328330.

I reached out to my tech contact and the 1621 pin box does have one hole that is slightly different than the 1621HD. The lower front hole is higher on the 1621HD box so you would need to drill one hole on each side of your mount to fit the Rota-Flex 1621 pin box.

expert reply by: Jason S

0

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Answer 1

The Trailair Rota-Flex 5th Wheel Pin Box - Lippert 1621 - 21,000 lbs #LC328329 does not have that rubber compound as a replaceable part option from the manufacturer. I called to confirm that was the case and they said the rubber compound is built…

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Answer 2

Thanks for the picture! That is exactly what I need to confirm what pin box your Forest River Shasta Phoenix 28RB has. I just spoke with my rep at Lippert and you have a 1621 pin box with an 18,000 lbs capacity. You will want the Gen-Y Hitch 5th…

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Answer 3

Thanks so much for that info, and yes, because your 2022 Forest River Sabre Cobalt 36BHQ has a Lippert 1621 pin box, the Gen-Y Hitch 5th Wheel to Gooseneck is a fit. The correct part number is the following: - Gen-Y Hitch 5th Wheel to Gooseneck Pin…

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Answer 4

A gooseneck adapter cannot be used with the Trailair Rota-Flex 5th Wheel Pin Box - Lippert 1621 - 21,000 lbs #LC328329 because of the excess play and movement that would be present at the connection point. You would instead need to swap out your…

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Answer 5

The Gen-Y Hitch 5th Wheel to Gooseneck Pin Box part #GY58GR is primarily designed for long bed trucks. It's no different than a standard fifth wheel pin box in regards to the size. If you were using a fixed hitch and standard pin box before with…

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Answer 6

Yes, the rubber cushion inside the Trailair Rota-Flex 5th Wheel Pin Box like part #LC328329 is essential to its functionality so if this is out of place or misaligned then that is certainly a cause for concern. That said, this is actually covered…

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Answer 7

According to Lippert, here is how you will need to install your Replacement Air Spring for Trailair 5th Wheel Pin Boxes #LC432404: "The bag is fastened at the bottom first by inserting the carriage bolt in the keyhole shape opening on the lower…

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Answer 8

I checked with our contacts at Trailair and the correct torque figure for the pivot bolt of your Trailair pin box is 50 ft lbs.

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Answer 9

I found the directions regarding how to replace the air spring in your Trailair Flex Air 5th Wheel Pin Box #LC328492 with the Replacement Air Spring #LC432404. According to the instructions: "The bag is fastened at the bottom first by inserting…

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Answer 10

I spoke to my contact at Lippert and the 15k Pin Box part #LC1191151 that you referenced weighs 104 lbs and the 21k Pin Box #LC1387882 weighs 115 lbs. The 21k would be the stronger one.

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Answer 11

I spoke with my contact at Lippert and although she wasn't able to provide me with the center of the king pin to first hole measurement, I do have the back of the mounting plate to center of the king pin measurement for you for the #LC328492.…

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Answer 12

The Trailair Flex Air 5th Wheel Pin Box part #LC369535 which is rated for 21,000 lbs is constructed of a thicker metal and also has beefier welds when compared to the Trailair Flex Air 5th Wheel Pin Box part #LC328492 which is rated for 18,000 lbs.…

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