How To Determine Which Pin Box I Have and What Replacements Are Available

Published 05/27/2015

Products Featured in This Question

Trailair Flex Air 5th Wheel Pin Box - Lippert 0719 - 18,000 lbs

(2)

$1442.52

Curt Flex Air 5th Wheel Pin Box - Lippert 1621 - 18,000 lbs

(185)

$1649.39

Question:

Hi, I have an LCI Trailair pin box but cant read the part number any longer. I would like to identify it for potential replacement parts in the future. Heres what I can identify on the pin box 1. Trailair P/N: ????4738 ...38 for sure 2. S/N: 019-000286625 3. Mfg. Date: 02/08/2011 Can you determine the part number from this information? Also, is it possible to retrofit the Lippart Trailair 1621 HD with a rotoflex pivoting head or Tri-glide air ride pin box to limit chucking? If yes, what would be the cost and part number? Thanks for your help!

asked by: Jim

Expert Reply:

I spoke with my contact at Trailair and from your serial number we were able to determine that your trailer came with a 1621 HD pin box which is a long pin box style. I was unable to obtain the exact part number for your Trailair pin box but from the picture that you provided, it looks as though someone may have replaced the original long style pin box with a medium style. In order to determine this you will just need to take a quick measurement from the back row of bolts to the center of the king pin. I have attached a diagram and an article regarding this measurement.

When it comes to a replacement pin box that will drastically reduce chucking, absorbs road shock, and minimizes bounce, I recommend going with the Flex Air which is Trailair's replacement for the Tri-glide model.

For example, if your 3b (marked in the picture) measurement equals 25-5/8 inch you have the long style pin box and could use the Trailair Flex Air 5th Wheel Pin Box, # LC328492, for a direct replacement.

If your 3b measurement equals 16-7/8 inch you have the medium style pin box and could use the Trailair Flex Air 5th Wheel Pin Box, # LC328484, for a direct replacement.

Prices are listed on each product's page.

expert reply by: Leah S