How Important Is The Shock Line on the Trailair Flex Air 5th Wheel Pin Box

Updated 03/13/2019 | Published 03/12/2019

Products Featured in This Question

Curt Flex Air 5th Wheel Pin Box - Lippert 1621 - 21,000 lbs

(192)

$1727.80

Replacement Pin Box Tank Valve for Lippert or UltraFab TrailAir Pin Boxes

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$46.54

Replacement Shock for Trailair Air Ride and Flex Air 5th Wheel King Pins - Qty 1

(82)

$76.66

Replacement Air Spring for Trailair 5th Wheel Pin Boxes - Qty 1

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$379.24

Question:

I just purchased a 2019 Forest River Riverstone 43foot fifth wheel weighing about 19,000 lbs which came with a Trail Air AIr Ride pix box. When I left with the unit new, the business I purchased it from could only get 115psi in the rubber bladder with the truck and trailer level and the trailer connected. This only brought the lower collar about half way up the yellow arrow and no where near the tip of the arrow which was where it was supposed to be. They told me this would be fine and might need more air in the future. The ride home was horrible and the trailer bounced back and forth terribly. My truck is a 2011 F350 SD 8foot bed dually using an Andersen hitch. I have not been successful getting a technician on the phone from Lippert and online it says the bladder can run up to 120 psi and I doubt 5 psi more than what I had would bring the collar to the proper level. SOOOO , how much air can I really put in this bladder to level it out and do so safely given the weight and size of my unit? Sorry to ask you when I didnt buy from you but Im trying to find someone who can advise be correctly. Thank you.

asked by: Kevin H

Expert Reply:

I spoke to my contact at Lippert about the issue you are having with the Trailair Flex Air 5th Wheel Pin Box like part # LC369535 on your 2011 Ford F-350. They stated that the arrow on the shock is just a reference point and not something that you should really use as your absolute guide as they have had issues with the sticker being misplaced. The reason that the ride is so rough is that you are at near max psi of the airbag which is 120 psi. They recommend that you adjust the pressure inside the airbag to around 70-100 psi without much consideration of the arrow on the shock. This should fix the issue you are having with the poor ride quality but if it does not or you need further clarification please just let me know.

The Trailair Flex Air 5th Wheel Pin Box is a very crucial part of your trailer therefore I highly adivse you keep spare parts on hand which I have attached a list of for you below.

Replacement Shock part # LC177223
Replacement Air Spring part # LC432404
Replacement Pin Box Tank Valve part # LC156740

expert reply by: Conner L