Best Pin Box Upgrade for a Lippert 1621 on a Grand Design Reflection 303RLS
Updated 07/11/2026 | Published 03/15/2018
Question:
I’m a new 5th wheel owner and I have purchased a Grand Design Reflection 303RLS. It currently has a Lippert 1621 pin box on it. What is the BEST replacement pin box that I can purchase. Money is not an object as I want whatever it takes for the BEST and SAFEST ride possible. Thank you,
asked by: Johnny M
Expert Reply:
The best replacement pin box for the Lippert 1621 on your Grand Design Reflection 303RLS is the Curt Flex Air. This pin boxes has an air spring and shock absorber which will reduce the back and forth chucking (stopping and taking off) and lower the shock from bumps. This not only helps to give you a great towing experience, but it also helps to reduce the vibration inside the coach.
To replace the Lippert 1621 on your Grand Design Reflection 303RLS you need the Curt Flex Air 5th Wheel Pin Box - Lippert 1621 # LC328492.
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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Rich P.
7/11/2026
Bought a Reese sidewinder kingpin number 68220 for our solitude 375. Will I be able to use that kingpin on a lighter reflection 303 or 373? Thanks so much.