Proper Inflation of the Curt Flex Air 5th Wheel Pin Box
Updated 08/27/2025 | Published 06/02/2022
Question:
I have a Trailair Flexair 18,000 gvrw pin box and have been inflating to 70 psi My question is - do you inflate the airbags when they are under load hooked up to the fifth wheel with landing gear up or when not loaded. The coach seems to ride well at 70 psi- is that the proper inflation? Thanks
asked by: Ted K
Expert Reply:
The Flex Air 5th Wheel, # LC328492 is to be inflated to between 20 and 120 psi. The pressure that works best for your specific arrangement and the current load is what determines the best pressure. Trying several different pressure setting and evaluating the ride quality is the way to make determination. Always maintain at least 5 psi in the system when not in use. You can inflate before or after making connection.
Product Page this Question was Asked From
Curt Flex Air 5th Wheel Pin Box - Lippert 1621 - 18,000 lbs
- 5th Wheel Pin Box
- Upgraded Pin Box
- Absorbs Road Shock and Reduces Chucking
- 18000 lbs
- Air Ride Suspension
- Fixed Turret
- Lippert 1621
- CURT
more information >
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on 5th Wheel Pin Box
Tom B.
8/27/2025
They can bottom out so make sure you don’t under inflate.