1. Fifth Wheel King Pin
  2. Lippert
  3. Fabex 730
  4. RBW 7019
  5. 21000 lbs GTW
  6. Upgraded Pin Box
Trailair Air Ride 5th Wheel King Pin - Fabex 730, RBW 7019 - 21,000 lbs

Trailair Air Ride 5th Wheel King Pin - Fabex 730, RBW 7019 - 21,000 lbs

Item # UF35-946215
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Our Price: $1,532.35
Fifth Wheel King Pin
This item qualifies for Free Truck Freight Shipping
Shipping Weight: 184 lbs
Quantity: 
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Experience smooth, stable towing with your fifth-wheel trailer by replacing your ordinary pin box with an air-ride-equipped model. The scissoring action of the coupler allows the interior air bag to absorb road shock so that you won't feel it. Call 800-298-1624 to order Lippert fifth wheel king pin part number UF35-946215 or order online at etrailer.com. Free expert support on all Lippert products. Guaranteed Lowest Price and Fastest Shipping for Trailair Air Ride 5th Wheel King Pin - Fabex 730, RBW 7019 - 21,000 lbs. Fifth Wheel King Pin reviews from real customers.
  • All Info
  • Reviews (84)
  • Q & A (29)
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  • Why etrailer?

Lippert Fifth Wheel King Pin - UF35-946215

  • Fabex 730
  • RBW 7019
  • 21000 lbs GTW
  • Upgraded Pin Box
  • Lippert
  • Absorbs Road Shock and Reduces Chucking
  • Fixed Turret

Experience smooth, stable towing with your fifth-wheel trailer by replacing your ordinary pin box with an air-ride-equipped model. The scissoring action of the coupler allows the interior air bag to absorb road shock so that you won't feel it.


Features:

  • Air ride pin box replaces standard pin box on your 5th-wheel trailer to enhance performance
    • Cushions and absorbs road shock
    • Improves handling and overall ride
    • Limits strain on truck and trailer frames
  • Scissor action allows pin box to compress, compensating for jarring and bounce
    • Internal air bag absorbs the road shock
    • Built-in spring ensures that pin box rebounds - keeps air bag from breaking down
  • Direct replacement for OEM pin box
  • King pin connects to any 5th-wheel trailer hitch
  • Sturdy steel construction


Specs:

  • Designed to replace the following pin boxes:
    • Fabex 730
    • RBW 7019
  • Weight capacity: 21,000 lbs
  • 1-Year warranty


Notes:

  • Not for use with any type of gooseneck adapter
  • Because of the size of this item, it ships via truck freight

Eliminate the bounce from your ride with the Trailair air ride coupler. The unique scissoring action of the pin box ensures that road shock is absorbed, preventing the harsh, rigid ride that you typically encounter while towing your fifth-wheel trailer. Not only does this improve your overall towing experience, but it also helps maintain a sound, well-functioning system. Less bounce and jarring means less stress on your truck, trailer and hitch.


Trailair Air Ride Coupler

How the Trailair Air Ride Works

When you encounter uneven terrain on your trip or hit a pothole on the highway, the Trailair pin box compresses, transferring the road shock to its internal air bag. A built-in air spring ensures that this compression occurs in a controlled fashion so that the air bag doesn't burst. It also causes the pin box to appropriately rebound, positioning it so that it's ready for the next bump in the road.



177696 Lippert Components (LCI) Trail Air Kingpin Box - M14

Replaces 35-946215 UltraFab Trail Air Kingpin Box - M14






Customer Reviews

Trailair Air Ride 5th Wheel King Pin - Fabex 730, RBW 7019 - 21,000 lbs - UF35-946215

Average Customer Rating:  4.8 out of 5 stars   (84 Customer Reviews)

Experience smooth, stable towing with your fifth-wheel trailer by replacing your ordinary pin box with an air-ride-equipped model. The scissoring action of the coupler allows the interior air bag to absorb road shock so that you won't feel it.

- LC155943
by:

Review from a similar Trailair in Fifth Wheel King Pin


I purchased this Lippert Air Ride hitch for my 40 foot Genesis Supreme trailer and wish I had bought it 2 years ago and installed it. What a difference is has made both in the trailer when towing as well as the difference in my truck while pulling it down the road. eTrailer had the best price and fast shipping. They as well helped me with verifying the right part number that works with my trailer. I purchase many parts and accessories from eTrailer and will continue to purchase from them in the future.


Comments
My hitch is working great! It has made a big difference in how well the trailer rides on my truck. No more harsh bumps when I drive over rough roads or poor bridge approaches. Awesome product!
Joe S - 06/23/2021


- LC155943
by:

Review from a similar Trailair in Fifth Wheel King Pin


Good looking product. Mounted it on a Montana 40ft 5th wheel. It arrived 2 weeks ahead of schedule. It was easy to install. I did have to grind the corners of the trailer frame bracket as the jaw hinge wouldn’t allow the bolt holes to line up. Once the corners were ground, everything lined up perfectly. It only took my son and I to pick up the pin box and once the first bolt was in, it was simple and easy to do the rest. There are 3 things to complain about. 1. The position of the air valve sucks. Really hard to get at. 2. The mark on the shock for proper inflation is not marked well. Had to get on hands and knees with a flashlight to actually see it. It was suppose to be bright yellow, it’s black, same as the shock. My 3rd complaint would be the fact that I had to drill 3 holes into the pin box to reattach the brake safety cable and the electrical wire box. The biggest positive thing is, is how much of a difference it has made in the ride quality for not only with the trailer but the truck as well. Soooo much smoother than the original pin box. Would I buy another one? You better believe I would. Wondering why I didn’t buy it sooner. Won’t have another 5th wheel without it.



- LC158778
by:

Review from a similar Trailair in Fifth Wheel King Pin


Added this pin box to improve ride and give my rv a smoother pull. The owners manual says you can use the orginal nuts and bolts, but felt getting new ones that are grade 8 was the best route for me. The pin box had several deep scratches due to shipping so I mounted it and then painted over the scratches and resolved the problem. The rebound shock didn't have the yellow arrow like the one in the pictures, does have an max inflation stamped in the shock but black on black doesn't help for proper inflation so I painted the arrow yellow, not great but it works. Number one issue is no matter the inflation of the airbag I can't get it too the top of the arrow as required. I checked the PSI on the airbag and was at 135 PSI. I felt that was too high of air pressure and there's nothing in the manual or online to say how much air should be in an airbag so I went with 98 PSI to be safe. As for the ride I feel it was an improvement over the previous pin box but to be honest my F450 has airbags as well, so was the improvement due to the pin box or because of the truck airbags. I'll go with both had factors with the ride. But the number 1 factor for me was the 21000 weight capacity. 4 out of 5 is the issue with inflation and what's correct.



- LC179879
by:

Review from a similar Trailair in Fifth Wheel King Pin


The Trailair fits the bill for us. We have a Beacon 5th wheel and sitting with the trailer level the pin box wings sit below the bed side rails. With the original Rotaflex or Reese goose box the wings would hit the side rails in a turn more than 50 degrees. With the shorter Trailair the wings don’t hit. We are using it with an Andersen Ultimate with the coupler forward of the pin.



- LC158778
by:

Review from a similar Trailair in Fifth Wheel King Pin


We ordered our Trailair Pin Box and it shipped and arrived earlier than expected. Great customer service and Excellent help with setup after installation.



- LC158778
by:

Review from a similar Trailair in Fifth Wheel King Pin


Really made a positive improvement in towing my RV. The hitch absorbs the shocks from the trailer when towing and therefore the ride is much better in the tow vehicle. I also think it works the other way as well, RV is somewhat shielded from shocks the tow vehicle is experiencing. Am so impressed that I moved it over to our new RV. Well worth the time and cost to buy and install.



- LC158777
by:

Review from a similar Trailair in Fifth Wheel King Pin


Great phone assist prior to ordering as always and product was just as described. Shipping was a little hard to track as UPS advised the unit was sitting in our town but unable to locate for 5 days. E-Trailer is always awesome to work with. Thanks to all your staff.



- LC158778
by:

Review from a similar Trailair in Fifth Wheel King Pin


The king pin has eliminated about 80% of the chucking. I pull 16k fiver. I am very happy with it. Related I always use etrailer for my parts purchase. One time I was stranded near Disneyland. I needed shackle. They had me triple check for correct part and rushed delivery. These guys are the real deal.



- LC158778
by:

Review from a similar Trailair in Fifth Wheel King Pin


What a big difference it has made. I was tired of the trampoline action but now it done so thank you for your timelyness in sending my order now I have to look at a Anderson hitch



- LC155943
by:

Review from a similar Trailair in Fifth Wheel King Pin


Have not did a road test yet but it’s installed. Way heavier than factory. I have talked to many that have this and like it. Helps reduce chucking back and forth movement. Nothing will be solve all if you are on a rough road you will feel it. No hitch will eliminate. Was fairly easy to install you will need help to lift. I used the tailgate on the truck and backed under and used blocking to get in place. I installed pretty much myself. My wife help some with aligning the bolts.



- LC155943
by:

Review from a similar Trailair in Fifth Wheel King Pin


Air Ride Pinbox arrived on time and in excellent condition. It is a perfect fit and was an easy installation. Thank You, Jack Herndon



- LC158778
by:

Review from a similar Trailair in Fifth Wheel King Pin


The trailair pin box I ordered and received looks be be everything I was told it would be. I have not bin able to road test the hitch yet as it's only early March and living in north east Minnesota, we still have about two feet of snow . I'm sure hoping it works as well as its supposed to.


Comments
I lovin the ride with this air ride pinbox. It works well for the ride on both truck and trailer, glad I decided to make the investment.
Dean s - 03/07/2021


- LC158778
by:

Review from a similar Trailair in Fifth Wheel King Pin


I love this AirRide by Trail-air. It provides an incredibly smooth ride on the road. You can adjust the amount of air for your ride, the Schrader valve is right on top of the unit and easy to access. My Trail air installed easily on my Forest River Sandpiper 372LOK mid bunk, especially with help from my Dad. This Trailair solved a big problem for me. I needed an extra couple of inches space between my 2018 Ford Super Duty DRW and the coach. My truck came with the Ford factory-installed Reese 27K hitch and I needed more clearance to allow the tailgate to drop without touching the coach. The kingpin on the Trailair sits at least 2” forward of the factory kingpin and provided that desperately needed space. It really makes for smooth and quiet ride ! etrailer folks were very helpful. The first unit was damaged by the freight company and when I notified them, etrailer sent another unit quickly. I will buy from etrailer whenever I can..


Comments
I still love the ride it provides- always smooth. Wouldn’t use a standard kingpin again. The airbags lose air over time- it’s my only complaint. Not enough to effect performance on a week-long trip but it loses air. I tightened the fill valve. Will re-tape the valve again if needed.
Bernie C - 05/26/2020


- LC155943
by:

Review from a similar Trailair in Fifth Wheel King Pin


This is my second trailair pin box and I just love them it takes all of the bouncing out of the truck in the camper and makes it a smooth ride. Shipping was great and product came packaged as good as possible.



- LC158778
by:

Review from a similar Trailair in Fifth Wheel King Pin


The ride is so much better. I also added air bags to my truck!



- LC158778
by:

Review from a similar Trailair in Fifth Wheel King Pin


This is the 2nd air ride hitch i've purchased. First one was on another 5th wheel and stupidly didn't keep it when I traded for the one I have now. They work great! It takes the shock out of the bumpy roads and keeps camper insides from re-arranging when traveling. Very happy with the hitch.



- LC179879
by:

Review from a similar Trailair in Fifth Wheel King Pin


I'm pleased with the pin box. Put it on my 5th. wheel. The airbag gives us a better ride than any other pin box. Its a great product.



- LC158778
by:

Review from a similar Trailair in Fifth Wheel King Pin


Had a great experience with etrailer ordered my air ride pin hitch and got a great part at a great price. Thanks everyone at etrailer I appreciate you all. Bryan



- LC155943
by:

Review from a similar Trailair in Fifth Wheel King Pin


etrailer did an awesome job to get my pinbox to me. They even price-matched [online retailers] best deal. Very happy with my purchase.



- LC158778
by:

Review from a similar Trailair in Fifth Wheel King Pin


Before installing the airride , dish's shifted and draws opened. Now with easy installation and running 10 thousand miles none of the old problems appeared. Warning, always before leaving check air shock to be at the top of the arrow on shock. Great product!



- LC155943
by:

Review from a similar Trailair in Fifth Wheel King Pin


Delivery was quick and product was as advertised. I called customer support (Danielle H) and she was extremely helpful and knowledgeable. Danielle helped me make sure I ordered the proper Trailair king pin based on dimensions of my current 5th wheel.



- LC158778
by:

Review from a similar Trailair in Fifth Wheel King Pin


Looks like a very good product, Easy installation only took an hour. Took it on a short test run On a very rough road It seemed to work well but we'll know more on the next upcoming trip. Packaging was inadequate could have used more Tie down straps , but no damage.etrailer is great to work with!!!



- LC158778
by:

Review from a similar Trailair in Fifth Wheel King Pin


Took all the transfer of trailer hunting out of tow vehicle as you travel. Also give me more turning clearance on short bed F250.



- LC158777
by:

Review from a similar Trailair in Fifth Wheel King Pin


etrailer is and excellent site to order parts for your trailer. They walked me thru the part numbers so the pin box I ordered fit. No problems with the install and I can't wait to take my first trip with the new pin box.


Comments
Awesome. I live on treacherous roads and this takes the bounse out of my trailers and helps keep the trailer from coming apart. I highly recommend this product.
David - 03/05/2020



- LC155943
by:

Review from a similar Trailair in Fifth Wheel King Pin


The TrailAir pin box is a good upgrade from an entry level unit. You have to learn what the ideal air pressure needs to be for your rig, ie, trial and error. The TrailAir calms the fifth wheel trailer quit a lot going over bridge entries and over rough roads. It would be nice if they would install a tee on the air inlet port with the air add fitting and an air pressure gauge so that one could see the actual bladder air pressure anytime.


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Show More Reviews

Ask the Experts about this Lippert Fifth Wheel King Pin

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    An aftermarket 5th wheel pin box that includes an air spring can improve your ride quality by taking some of the bumps out of your towing day. You can select a suitable cushioned pin box by noting the part number of your current pin box; usually this is found on the safety sticker on the left side of the box. Once you know your pin box number you can use the linked page to see the available models that will bolt up in its place. For example, if you have the popular Lippert 1621 then...
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  • Recommended Air Pressure in Air Bag of Trailair Air-Ride Pin Box
    The pressure in the airbag of the # UF35-946215 Trailair Pin Box can range from 20 to 120 psi depending on your situation. Once the pin box is installed, hitch the trailer to the tow vehicle on level ground. There is a sticker on the front of the shock absorber on the pin box. You should inflate the air bags until the bottom lip of the top shroud on the shock absorber is even with the arrows on the decal. TrailAir states keeping the ride level maintained at a certain level is the most...
    view full answer...
    Image 1 for
  • Replacement Trail Air Pin Box for a Fabex PB730H 5th Wheel
    Yes, the Trailair air ride fifth wheel king pin # UF35-946215 will replace your current Fabex PB730H pin box. The Trailair will improve your handling and the maximum weight capacity is 21,000 pounds.
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  • Can a Reese Revolution Pin Box be Replaced with Trailair Pin Box
    Can you get the pin box number off of the Revolution? You should see something like LIPP 1621 or Lippert 1621 or 1716. With that info we can determine which Trail Air you would need. Or if you see Fabex 730 or RBW 7019 the part # UF35-946215 you referenced would be a fit. It's interesting that you want to go from the Revolution to the Trailair. Typically the Revolution/Sidewinders are the most preferred pin box style and are what people switch to and not from.
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  • Install Instructions for Trailair Air Ride 5th Wheel King Pin Fabex 730, RBW 7019 21K UF35-946215
    Yes, I can help you out. Below are the installation instructions for Trailair Air Ride 5th Wheel King Pin - Fabex 730, RBW 7019 - 21,000 lbs Item # UF35-946215. Step 1) The Trailair pin box is installed in two main sections, upper body and lower jaw. Level trailer front to back. Measure old box from bottom of the kingpin plate to the ground. Add 9.5” to this measurement and that will be the height of the top flat area of the upper body to the ground. Remove old pin box. Care should be...
    view full answer...
  • How To Locate Air Leak On Trailair Air Ride 5th Wheel King Pin
    I called my contact at Trailair and they told me that it can sometimes take 2 hours before a customer notices the air leaks in a system like part # UF35-946215. There are a couple things you can do to locate the problem. The first thing you can do is remove the air valve on the top of the unit and make sure it is clean and free of any dirt or corrosion. Then use some plumbers tape on the threads to make sure when it is installed it is air tight. If the system still leaks air, you can...
    view full answer...
  • Pin Box Replacement Recommendation for a Lippert 1116 to Reduce Chucking
    For a cushioned pin box to replace your Lippert 1116 pin box I would recommend the Trailair Glide part # LC155943 as it has been confirmed as replacement fit. Integrated steel rollers allow the bottom jaw to glide, reducing the push and pull that is typical in fifth-wheel towing. The internal air bag cuts down on bounce by absorbing road shock. The Trailair Tri-Glide works to defeat this troublesome occurrence by incorporating steel rods into the bottom of the pin box. These three...
    view full answer...
  • How Much Air Pressure Should Trailair Cushioned Pin Box Have
    The Trailair Air Ride 5th Wheel Pin Box # UF35-946215 has an air pressure range between 20 and 120 psi and the amount of air you'll need to use will be determined after you hook your trailer up to your hitch. This will be indicated by a sticker located on the front shock and not by a specific psi. You will simply line up the lower part of the shock's outer tube with the top of the sticker. I've attached some photos to assist.
    view full answer...
    Image 1 for
  • Trailair Air Ride 5th Wheel King Pin Pressure When Storing
    The air pressure on the Trailair Air Ride 5th Wheel King Pin - Fabex 730, RBW 7019 - 21,000lbs Item # UF35-946215 will gradually decrease over time, which is why the manufacturer states that you should check the pressure before each use. From what I've read from owners of this king pin the pressure typically holds for 2-3 weeks before needing to be filled up again. The environment you're in can affect this of course. So you can relieve the pressure if you want or leave it alone and it will...
    view full answer...
  • Troubleshooting Air Pressure Loss in my Trailair Pin Box
    The air bag in the Trailair Air Ride 5th Wheel King Pin part # UF35-946215 will seem to feel different when the camper is attached to the truck and can feel slightly softer after it is disconnected. It shouldn't loose any pressure. If you unhook the trailer and measure it at 30 psi it should be at 30 psi the next day as well +/- a lb. or so for temperature difference. If this is what is happening fill the bag to about 50 psi and spray with a soapy water solution to see where the leak...
    view full answer...
  • What is Minimum Clearance Between Fifth Wheel Overhang and Bed Rails of Truck
    The minimum distance you want to have between the overhang of a fifth wheel trailer and the bedrails of a truck is going to be 6 inches. Some argue it's only 4 inches but 6 inches is really the safest minimum number to go with. You can adjust the height of the fifth wheel hitch head and the pin box in the frame of the trailer typically to allow you to get this clearance. But you also have to keep in mind that the trailer needs to be kept as level as possible too.
    view full answer...
  • Recommended PSI For A Lippert Air Ride 5th Wheel Pin Box
    There isn't a set PSI for the Trailair Air Ride 5th Wheel King Pin - Fabex 730, RBW 7019 - 21,000lbs Item # UF35-946215. On the front of the pin box there is a shroud that wraps around the air shock absorber tube that will match right up to the tip of the arrows when the correct PSI is reached.
    view full answer...
    Image 1 for
  • Measurements Of Trail Air Ride 5th Wheel King Pin # UF35-946215
    I went out to our warehouse and took some measurements for you of the Trailair Air Ride 5th Wheel King Pin - Fabex 730, RBW 7019 - 21,000 lbs # UF35-946215. Probably the most helpful measurements are: From the bottom of the king pin to the top of the air spring the measurement is 13 inches. From the bottom of the king pin to the top of the shock on the front is roughly 14-1/2 inches From the base where the hitch plate connects to the center of the first bolt hole is 9-1/2 inches. I've...
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    Image 1 for
  • Should an Air Ride/Air Bag Pin Box Be Used when Towing 5th Wheel with Peterbilt Rig
    Typically, 5th wheel pin boxes with airbags are used when someone wants to improve the ride quality of the tow vehicle while pulling the trailer. You can certainly use a pin box with an air bag to help reduce the stress on your trailer while towing with your rig, but the stress reduction will likely be minimal. An air ride pin box will not provide a noticeable difference in ride quality with your rig. If you decide to replace your existing pin box with an air ride pin box, you will...
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  • 5th Airborne Premium Fifth Wheel Air Ride Coupler To Replace RBW 7026
    In my research I was unable to find 7026 as one of the RBW model pin boxes. It's possible the last number has worn off and what looks like a 6 is really an 8. You may want to check the number again to make sure it that isn't the case. If you find you have a 7028, which is a fairly common one, the replacement is part # UF35-946212. If you can't make out the last number for sure, you will need to measure the mounting holes to find the right replacement. I have attached a helpful article...
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  • Pin Box Replacement for RBW 7028 That Allows Additional Turning Clearance
    I can't find any record of an RBW 7026 pin box. I wonder if you have a 7028 instead and the number as you read it has been damaged making the 8 look like a 6. The 7028 is a very common pin box and the perfect solution for it (and you) would be to replace it with a Sidewinder part # RP61412. This will move the pivot point back 22 inches which will allow you to make sharp turns with your short bed truck. The Sidewinder pin boxes were designed for exactly what you are trying to do.
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  • Can a Welded-On Capture Plate be Cut Off of a TrailAir M14 Pin Box
    If you were to take a torch or grinder to the pin box you run the risk of damaging or weakening the skid plate. If you wanted to do that I would have it done by a professional welder to ensure that the skid plate is not damaged. Ideally though you would replace the TrailAir pin box with a new one, # UF35-946215.
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    Image 1 for
  • Solution for Chucking with 2016 Rockwood Forrest River 5th Wheel
    Thanks for the part number of your Reese Revolution Pin Box. I was able to do some digging on it and found that it is a specific Revolution made for your trailer that is narrower than most pin boxes at 10 inches (most are 12 or 12-1/2 inches). Because of that Lippert does not have any Trailair pin boxes that are a fit for it. We also got confirmation of this from Lippert. That being said, in nearly all cases of chucking the actual problem is the fifth wheel hitch. Upgrading to a fifth...
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  • How to Select Correct 5th Airborne Cushioned 5th Wheel Pin Box to Reduce Jarring and Chucking
    To reduce jarring and chucking when towing your Weekend Warrior 5th wheel toy hauler with your 2017 Ford F-350 dually you can potentially replace the trailer's standard pin box with an aftermarket cushioned model that will take away some of the roughness. Please refer to the linked article. We'll need to find out the part number of the OEM pin box (king pin) that is on the trailer now in order to know the correct replacement. All models we offer are displayed on the linked page; select...
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  • Fit of Trailair UF35-946215 Air Ride Replacement Pin Box on 415 Raptor 5th Wheel
    Air Ride pin boxes aren't RV specific, they're specific to the OEM pin box used by the manufacturer when your 5th wheel we manufactured. All the OEM pin boxes use a different bolt pattern, so it's crucial to identify which one you have. The air ride pin box you need will depend on the manufacturer and model number of the OEM pin box on your 5th wheel. The pin box will have a sticker or ID plate on it somewhere that lists the manufacturer and model number. The # UF35-946215 Trailair...
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  • Availability of TrailAir Cushioned Pin Box to Replace Lippert Unit on 2007 Keystone Cougar 310SRX
    Compatible replacement 5th wheel pin boxes are determined based on the original item's part number. Lippert's most popular pin boxes are their 1621, 1621HD and 1716 models and these part numbers usually appear on the sticker located on the driver's side of the pin box. Once you know your pin box part number you can check for available replacement units like the TrailAir Flex Air # LC328492, for example, which bolts right up in place of a Lippert 1621. The linked page displays all...
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  • Availability of Trailair Tri-glide to Replace RBW 7019 Pin Box
    The Trail Air air ride pin box that would replace your RBW 7019 pin box on your fifth wheel would be part # UF35-946215. You can see current pricing on the product description page I've linked for you. Having a good 5th wheel hitch that utilizes a wrap around jaw to firmly hold the king pin would go a long way to reduce chucking. The standard Air Ride pin box will offer a noticeable improvement in ride quality over an OEM pin box. If you would like to upgrade your fifth wheel hitch,...
    view full answer...
  • Is Tri-Glide Pin Box Available To Replace Fabex 730 Pin Box On Fifth Wheel Trailer
    The fifth wheel pin box we offer that is designed to replace the Fabex 730H you currently have is the Ultra-Fab Trailair Air Ride 5th Wheel King Pin, part # UF35-946215. This is a 21,000 lb capacity pin box that has an internal air bag to absorb road shock. We do not offer a Tri-Glide pin box that will work with the Fabex 730.
    view full answer...
  • How to Determine Fifth Wheel Pin Box Model
    If you are unable to contact your trailer's manufacturer with your VIN to find the factory pin box model number there are some steps you can take which will allow you to determine what pin box model you have so you can purchase a new FlexAir. To do this you will need to follow the steps in the linked help article, which I will go over with you. Start by selecting your pin box style like in the accompanying photo (which you will also find in the help article). You will then need to use...
    view full answer...
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  • Can a Gooseneck Adapter be Used on a Trailair Air Ride Pin Box
    You can use the Convert-A-Ball Cushioned 5th-Wheel-to-Gooseneck Adapter # CAB-C5G if you change out your pin box, but unfortunately the Trailair Air Ride # UF35-946215 that you have cannot be used with a gooseneck hitch adapter. We do have some options for you to use a 5th wheel hitch like the B&W Companion # BWRVK3500 in a B&W gooseneck hitch but I would need to know what brand gooseneck hitch you have to verify a fit.
    view full answer...
  • 5th Wheel Cushioned Pin Box to Replace Fabex 730
    We do offer a cushioned 5th wheel pin box that is a direct bolt-on replacement for the Fabex 730, the Trailair Air Ride 5th Wheel Pin Box # UF35-946215. This cushioned pin box is rated for 21K and it will substantially reduce bounce when you tow and also reduce road shock. It will not require any drilling for installation. I also linked our page showing trailer suspension enhancement kits like the Dexter E-Z Flex # K71-652-00 and the Lippert Equa-Flex # LC279688 as well as some help...
    view full answer...
  • Comparing Longevity of Reese and TrailAir Cushioned 5th Wheel Pin Boxes
    The cushioned 5th wheel replacement pin boxes we offer, including Reese and TrailAir items, are all shown on the linked page. Like you, I take note of the major difference in the warranty coverage between these brands and if it were me that difference would matter. I can also suggest that for your assessment of these products you check out the reviews posted by our customers that have purchased these products from us. On each item's page you can click on the review link next to each photo....
    view full answer...
  • Using 21,000 lb Rated Fifth Airborne Air Ride Pin Box on 6,400 GVWR 5th Wheel
    All of the 5th Airborne and TrailAir air ride pin boxes we offer as replacements for the RBW 7019 pin box are rated for 21,000 lbs. Although the capacity of the pin box is much higher than gross weight of your fifth wheel, it will not cause any problems. The bolt pattern used to connect your existing RBW 7019 pin box is specific to that model, so unfortunately using a different lower rated replacement pin box will not work for you. The Ultra-Fab TrailAir Air Ride 5th Wheel Pin Box, part...
    view full answer...
  • Cushioned Replacment Fabex 730 Pin Box
    If yours is broken it's time for a new one as there isn't a safe way to repair them. We have a replacement cushioned pin box to replace the Fabex 730 model you have on your trailer currently with the Trailair part # UF35-946215. This will bolt right up to what you have and give you a cushioned ride that will make towing much more enjoyable. This also has the same 21k capacity as your old pin box.
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