What are Available Capacities for Lippert Rota Flex Pin Boxes to Replace 1621 Pin Box
Updated 03/15/2018 | Published 03/13/2018 >
Products Featured in This Question
Question:
Whats the difference the 18k vs and 21k? Is the 21k heavier or built stronger? They look exactly the same so Im not sure where the extra strength comes from. I have the 18k version and since Im pulling a trailer behind the 5th wheel, Ill be at about 18400 and may need the 21k version. What do you think?
asked by: Clarendon T
Expert Reply:
For Trailair Rota-Flex pin boxes that fit as a replacement for a Lippert 1621 we have the 21k part # LC328329 and we have the # LC328330 which it sounds like you have. I can assure they aren't both really rated for 21k and the only difference is a part number and a few stickers. While the differences are hard to see by just looking at pictures of the two the 21k version is reinforced in areas you can't see and does have a higher capacity.
If you are going to be over the 18k capacity of your current pin box, even by 400 lbs we have to recommend you upgrade.
Product Page this Question was Asked From
Curt Rota-Flex 5th Wheel Pin Box - Lippert 1621 - 21,000 lbs
- 5th Wheel Pin Box
- Upgraded Pin Box
- Absorbs Road Shock and Reduces Chucking
- 21000 lbs
- Rubber Spring Suspension
- Fixed Turret
- Lippert 1621
- CURT
more information >
Featured Help Information
Instructions
Continue Researching
- Search Results: 7 way cord 7 way rv
- Shop: Trailer Wiring
- Video: The Low-Down on the Curt Rota-Flex 5th Wheel Pin Box
- Shop: Mighty Cord 7-Way RV Style Trailer Connector w/ Molded Cable - Trailer End - 8' Long
- Q&A: Solution for Hitch Noise of Roto-Flex Pin Box Trailer Towed with Curt Q20 Hitch
- Q&A: Dimensions of the Rota-Flex 5th Wheel Pin Box # 328330
- Shop: Trailair Rota-Flex 5th Wheel Pin Box - Lippert 1621 or 1621HD - 18,000 lbs
- Shop: Curt Rota-Flex 5th Wheel Pin Box - Lippert 1621 - 21,000 lbs
- Search Results: 7 pin connector cable
- Q&A: Recommended 5th Wheel Base Rails for a 2024 GMC Sierra 3500
- Shop: Curt 5th Wheel/Gooseneck Custom Wiring Harness w/ 4-Way and 7-Pole Connector - 7' Long
- Search Results: trailer hitch
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Shop: Curt Powered Tail Light Converter with 4-Pole Flat Trailer Connector
- Article: Trailer Wiring Diagrams
- Shop: Trailer Hitch
- Video: How to Choose a Trailer Brake Controller
- Q&A: What is the Difference Between a 4-Way and 7-Way Trailer Connector
- Video: The Low-Down on the Curt Powered Tail Light Converter with 4-Pole Flat Trailer Connector
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Search Results: trailer wiring
- Shop: Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
- Shop: Suspension Enhancement
- Video: Curt T-Connector Vehicle Wiring Harness Review C56040
- Shop: Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Search Results: trailer tires and wheels
- Q&A: Lug Nut Torque Chart for Trailer Wheels
- Q&A: Installation Time for Blue Ox BX1128 Flat Tow Base Plate Kit for 2016 Jeep Grand Cherokee
- Article: How to Measure for Trailer Hitch Drop

