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  1. Fifth Wheel King Pin
  2. Lippert
  3. Lippert 1621HD
  4. 21000 lbs GTW
  5. Absorbs Road Shock and Reduces Chucking
  6. Upgraded Pin Box
Trailair Air Ride 5th Wheel Pin Box - Lippert 1621 & 1621HD - 21,000 lbs

Trailair Air Ride 5th Wheel Pin Box - Lippert 1621 & 1621HD - 21,000 lbs

Item # LC158778
Retail:$1,948.12
Our Price: $1,347.38
You Save: $600.74
Fifth Wheel King Pin
This item qualifies for Free Truck Freight Shipping
Shipping Weight: 184 lbs
Quantity: 
In Stock
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Product Expert Kathleen M

Is this right for you? Product Expert Kathleen M says:

Yes, if you:

  • Like having the "Cadillac" option - RVers with this pin box say it feels like their fiver is floating over the road
  • Often drive over very rough roads and want to save your truck and trailer (and yourself!) from getting beat up by all the bumps and dips

No, if you:

  • Have little space between the pin box and the nose of your trailer which can make monitoring and maintaining the pressure in the air bag a chore
  • Use a gooseneck adapter to tow your fifth wheel
  • Haul a trailer that weighs over 20,000 lbs
Enjoy smooth, stable towing with your fifth-wheel trailer by replacing your ordinary pin box with this air-ride-equipped model. An internal air bag and built-in strut absorb road shock so that you won't feel it. Replaces Lippert 1621 pin boxes. 1-833-496-1390 to order Lippert fifth wheel king pin part number LC158778 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 Pin Box - Lippert 1621 & 1621HD - 21,000 lbs. Fifth Wheel King Pin reviews from real customers.
  • All Info
  • Reviews (118)
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  • Why etrailer?

Lippert Fifth Wheel King Pin - LC158778

  • Lippert 1621HD
  • 21000 lbs GTW
  • Absorbs Road Shock and Reduces Chucking
  • Lippert
  • Upgraded Pin Box
  • Fixed Turret

Enjoy smooth, stable towing with your fifth-wheel trailer by replacing your ordinary pin box with this air-ride-equipped model. An internal air bag and built-in strut absorb road shock so that you won't feel it. Replaces Lippert 1621 pin boxes.


Features:

  • Air ride pin box replaces standard pin box on your 5th-wheel trailer to cushion your ride, improve handling, and limit strain on truck and trailer
    • Minimizes chucking
    • Eliminates bounce and jarring
  • Internal air bag absorbs road shock
    • Scissor-like motion allows pin box to compress, compensating for jarring and bounce
    • Built-in shock ensures that pin box rebounds - keeps air bag from breaking down
  • Black powder coat provides rust resistance
  • Sturdy steel construction
  • King pin connects to any 5th-wheel trailer hitch
  • Bolt-on installation with no assembly required
  • Made in the USA


Specs:

  • Designed to replace Lippert 1621 and 1621HD long-jaw 5th-wheel pin boxes
  • Weight capacity: 21,000 lbs
  • Length (from outside edge of mounting plate to center of king pin): 28-11/16"
  • 1-Year limited warranty


Note: Do not use the Trailair air ride pin box with any type of gooseneck adapter.


Getting there is half the fun, right? Not if you're being bumped, jerked, jammed, and pushed around from the chucking and road shock that occurs as you tow your fifth-wheel trailer or RV. And imagine the costly wear and tear on your trailer as it endures that rocky ride.


Put the fun back into your trip and ease the stress on your trailer by replacing your factory pin box with the Trailair air ride pin box. The internal air bag and built-in shock work together to cushion your ride, improve handling, and limit strain on both your truck and your trailer.


Air Bag Absorbs Road Shock

Lippert Trailair air ride pin box air bag and shock

Standard pin boxes without any type of shock absorption transfer road shock to your trailer, resulting in potential damage to the trailer and an overall bumpy ride. But the Trailair air ride pin box absorbs shock and cushions your ride as you pull your fifth-wheel trailer. When you encounter uneven terrain on your trip or hit a pothole on the highway, the Trailair pin box compresses vertically, similar to how a pair of scissor blades closes in on each other. This compression transfers the road shock and vibrations to the internal air bag, saving your fifth-wheel hitch, trailer, or tow vehicle frame from enduring a rocky ride.


A built-in strut, or shock, controls the Trailair's compression so that the internal air bag doesn't burst. The strut also causes the pin box to appropriately rebound without any bounce, and positions it to be ready for the next bump in the road.


Simple Setup and Installation

First, simply remove your existing Lippert 1621 or 1621HD pin box from your trailer. The Trailair uses the same bolts that held on your original pin box so no additional hardware is required for installation. Plus, the Trailair pin box comes out of the box ready to be put on your trailer, so no assembly is needed. Because the Trailair is quite heavy, you should put it on an elevated surface or have a friend help you support its weight during installation.


Lippert Trailair air ride pin box air intake valve and inflation indicator

The internal air bag should be inflated after the pin box has been mounted on your trailer. Using the air intake valve, inflate the air bag until the outer cylinder of the shock rises high enough to fully expose the yellow inflation indicator sticker.



158778 Lippert Components (LCI) Air Ride by Trail Air Fifth Wheel Kingpin Box for Long Jaw Lippert 1621 and 1621HD

Same as 35-946203 Ultra-Fab Air Ride Trail Air Kingpin Box

Replaces 171200





Customer Satisfaction Score:


Customer Reviews

Trailair Air Ride 5th Wheel Pin Box - Lippert 1621 & 1621HD - 21,000 lbs - LC158778

Average Customer Rating:  4.7 out of 5 stars   (118 Customer Reviews)

Enjoy smooth, stable towing with your fifth-wheel trailer by replacing your ordinary pin box with this air-ride-equipped model. An internal air bag and built-in strut absorb road shock so that you won't feel it. Replaces Lippert 1621 pin boxes.

by:

I’ll start from the second I ordered this online. Confirmation email, then within days a shipping confirmation. When I ordered my shipping said 2 weeks out for delivery. I got the item in 9 days. The communication from the freight service was top notch. Unlike, some reviews the item was in great condition when it arrived. On a pallet in a box. No complaints. The driver even let me back up to his lift gate and help me slide the item into my truck for easier install. I had previously removed the factory hitch box prior to arrival so when the upgraded item arrived I was ready for install. Took about an hour to line everything up. Used a jack in the truck bed to help lift item where I needed it. I haven’t towed with it yet, that’ll be next week. But it looks beastly and like it’ll be a much more comfortable ride for me and my truck. Very happy so far, will leave an updated review after an out of state trip next weekend. etrailer was great. First item Ive ordered from you all but I’ll be back. Thank you!! Happy customer!!




by:

With the help of my wife, I had the Flex Air pin box installed within 1.5 hours. Used a floor jack on top of my pickup tailgate.




by:

Our fifth wheel experienced pin box cross frame cracking while on a trip. After having it properly repaired I decided to invest in the Trail-air pin box to alleviate the shock and harsh pounding from our lousy roads. I purchased from etrailer.com and installed it myself. Being only a 29 foot 5th wheel the tounge weight is low so after experimenting with pressures I run 40 psi in it and it flexes when hitting bumps or dips taking the stress off the trailer. Tows like a dream. Knowing what I know now I would have bought and installed it when I bought the 5th wheel and saved a repair during a trip. It is expensive but well worth it.




by:

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.


Comments
Its been a year since last review, still havent had any issues with the pin box. Works well and provides a smooth ride under most conditions. If you run into rough patches on the road youll feel it and in my opinion there isnt anything made today that will eliminate that type of chucking. I also have airbags on my truck and it still happens. Now for the pin box 1. It works as advertised and improves the ride substantially. 2. The pin box is very well built and no issues period. 3. One issue is the air valve on top of the pin box which makes you get up into the truck bed to fill it with air. What would be a improvement would have a extension that attaches to the valve that would allow you to add air without having to get into the truck bed. To summarize, this pin box has been a great investment and if youre looking a replacement box, youll be happy you purchased this one.
David M - 03/04/2022


by:

Can’t believe what a difference it made. Pulling a 38’ Avalanche with a 2019 Ram dually and we now glide over formerly rough bridge approaches. I’m 76 and my brother-in-law is 69 and we installed it at our RV Park in about 20 minutes! That included removing the old one! Recommending it to all my friends!




by:

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.




by:

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


Comments
Makes hook up a snap!
Dale H - 10/05/2021


by:

You shipped the wrong kingpin!!! I had mega problems shipping it back to you, while your company held my payment, until you received the incorrect Kingpin back, all due to your company’s error!! That is why I will no longer do busywigh you!




by:

I noticed a much better ride inside my truck after installing my 5th wheel pin box.




by:

Stout, quality pin box. Quick shipping and great service. The final condition of the shipping container and some heavy scaring on the pin box left much to be desired from the freight carrier, but scuffs don't effect the functionality of the component.




by:

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


by:

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!!!




by:

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




by:

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




by:

Does help lessen impact of chucking on most roads. Unfortunately even this unit is no match for the s**t roads in central CA from Bakersfield to Modesto.




by:

The package arrived with installation parts missing. It was very disappointing. etrailer was notified and sent another package, hopefully this time with all parts needed for installation.




by:

Have the Lippert Components Trailair fifth wheel king pin installed on our 40 foot Big Country has made the difference in pulling the trailer down the road. I would recommend the King Pin if pulling a fifth wheel trailer. Now we don't even know it behind us. Great Product.




by:

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.




by:

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!




by:

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


by:

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




by:

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.




by:

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




by:

Every thing went Like you said it would .It was in very good shape with no damage .Going to put it on my RV and see how it works. Thank you


Comments
It was the best ride I every had .Wish I did it a long time ago
Jay - 02/17/2022


by:

This is the second Trailair hitch I have purchased. Fast shipping and easy to install on our new DRV Fullhouse JX390. Much better than the Mor-Ryde hitch DRV uses. Now no bounce in the truck on rough roads.



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See what our Experts say about this Lippert Fifth Wheel King Pin

  • Can the Anderson Ultimate be Used with the Trailair Air Ride 5th Wheel Pin Box
    If I am not mistaken, Anderson will allow for a cushioned pin box to be used with their Anderson Ultimate 5th Wheel Hitch that attaches to a gooseneck hitch like the B&W Turnoverball Underbed Gooseneck Trailer Hitch. I would double check with them but yes, you should be able to use the Trailair Air Ride 5th Wheel Pin Box part # LC158778 with the Anderson Ultimate even through Lippert does not recommend doing so.
    view full answer...
  • Will TrailAir # LC158778 Replace Lippert 1621HD on Big Country Fifth Wheel
    The 21k Trailair Pin Box part # LC158778 dimensionally will be an exact replacement for the Lippert 1621HD pin box that you have installed on your trailer currently. This will fit and work well for you. The height shouldn't be affected, but if for some reason it was you could use a different set of mounting bolts on the frame of your trailer when you install this pin box to get around that.
    view full answer...
  • Determining Torque Specs for Installing Trailair Pin Box
    Pin box bolt torque is based on the size of the bolts. 1/2 inch Bolts GR5 90 ft-lbs 5/8 inch Bolts GR5 150 ft-lbs 3/4 inch Bolts GR5 275 ft-lbs The specific torque specs for installing the Trailair pin box part # LC158778 that you referenced are listed in the included instructions that come with this.
    view full answer...
  • Are Fifth Wheel Tailgates Needed When Towing Trailer with Air Ride Pin Box
    Fifth wheel tailgates aren't installed on trucks for additional clearance for towing a 5th wheel trailer. An air ride style pin box like the Trailair part # LC158778 wouldn't need a fifth wheel tailgate anymore than standard pin box. The fifth wheel tailgates generally are used so that you can back up to your trailer without having to drop the tailgate and then lift it back up into place. Since the pin boxes pivot on the hitch head around corners the clearance gained by a fifth wheel tailgate...
    view full answer...
  • Do Trailair Pin Boxes Need to be Deflated Prior to Or After Connecting to Hitch
    You do not need to deflate the bag at any point with a Trailair like the part # LC158778 that you referenced. It would not need to be deflated prior to or after connecting to a trailer.
    view full answer...
  • Correct Capture Plate Needed for TrailAir Air Ride to Use With Pullrite 5th Wheel Hitch
    In order to use a TrailAir Ride 5th Wheel Pin Box like the # LC158778 you will need to measure the the width of your pin box (A) and the distance from the leading edge of the king pin to the leading edge of the king pin plate (B). If your measurements are A = 13-3/8" and C = 7-3/8" you will need part 331758 which can be obtained from Pullrite.
    view full answer...
  • Is the Trailair Air Ride 5th Wheel Pin Box Shipped Strapped To a Wooden Pallet
    Yes, the Trailair Air Ride 5th Wheel Pin Box part # LC158778 is shipped strapped to a wooden pallet so you can use the fork lift to install it on the trailer. The use of a fork lift will make installing the pin box much easier and this is both the method we recommend and use ourselves.
    view full answer...
  • Correct Trailair Flex Air 5th Wheel Pin Box for a 2020 Jayco Eagle 317 RLOK
    The correct Trailair Flex Air 5th Wheel Pin Box to replace the MORryde Rubber Pin Box on a 2020 Jayco Eagle 317 RLOK is part # LC158778. I verified this with Jayco for you as well.
    view full answer...
  • How to Determine Which Trailair Air Ride Pin Box Will Replace My Current Pin Box
    In order to determine which Trailair Air Ride pin box you can use to replace the standard pin box on your 2014 Cyclone toy hauler, you'll first need to determine which model pin box you currently have. Normally there will be a spec sticker or some sort of identifying plate/sticker on the pin box itself that will tell you the model number. For reference, Trailair # LC158778 you were looking at can be used to replace Lippert 1621 and 1621HD pin box models. If you can't find any model number...
    view full answer...
  • Will the Trailair Air Ride 5th Wheel Pin Box Work With a Standard Tailgate
    The Trailair Air Ride 5th Wheel Pin Box part # LC158778 has roughly the same overall dimensions as the pin box it will be used to replace so you should not have any problem with hitting the tailgate so long as you have the recommended clearance which is roughly 4-6" from the loft to the bedside. Therefore, if you didn't have any issues with the pin box and tailgate hitting below then you would not after installing the Trailair Air Ride 5th Wheel Pin Box.
    view full answer...
  • Initial Air Bag Setup on the Trailair Air Ride 5th Wheel Pin Boxes
    There is an adjustment to make when initially setting up the Trailair Air Ride 5th Wheel Pin Box part # LC158778 if the initial air bag position does not allow for the maximim PSI rating to get the pin box up to the appropriate level. To make the adjustment you release all air from the air bag, loosen its positioning bolts and then move it closer to the rear of the camper or further away from the pin. This provides the air bag more leverage inside of the pin box and will allow it to be...
    view full answer...
  • Length of Lippert Trailair Air Ride 5th Wheel Pin Box LC158778
    The Lippert Trailair Air Ride 5th Wheel Pin Box # LC158778 is intended to replace either of two specific OEM pin boxes, a Lippert 1621 or 1621HD, and measures 28-11/16-inches from the rear outside edge of the mounting plates to the center of king pin. You can see this in the linked photo and compare to your current pin box. This king pin includes an air spring and shock that will eliminate much of the chucking and road shock you feel now with your OEM pin box and not only will it cushion...
    view full answer...
    Image 1 for
  • How To Determine Which Trailair Air Ride Pin Box Is Correct for a Forest River RV Wildcat 32WB
    I do have a way for you to find this information but I don't know what model pin box you have on your 2019 Forest River RV Wildcat 32WB. There should be a sticker on the side of the wing set where the pin box attaches which will tell you the serial number of the pin box which I can then use to confirm the correct model. The most common is a Lippert 1621 and if this is what you have then the correct Trailair Air Ride 5th Wheel Pin Box for this is part # LC158778.
    view full answer...
  • Do Lippert Pin Boxes Have A Certain Pin Weight Capacity
    The Trailair Air Ride 5th Wheel Pin Box does not have a pin weight capacity figure according to Lippert. Typically a trailers pin weight is 20% of the total weight of the trailer. That means your trailer should weight around 15,500 lbs. Trailair Air Ride 5th Wheel Pin Box - Lippert 1621 & 1621HD part # LC158778 is rated for trailers that weigh up to 21,000 lbs so this pin box is properly rated for your trailer if you are replacing a Lippert 1621 and 1621HD long-jaw 5th-wheel pin boxes....
    view full answer...
  • TrailAir Flex Air Hitch for a Road Warrior 355 5th Wheel Toy Hauler and 2015 Ford F-250
    I recommend the Trailair Flex Air 21k, part # LC158778 for your Road Warrior 355. This hitch is designed to reduce bouncing, jarring and chucking of your ride and help reduce passenger fatigue. I reached out to Lippert and confirmed that the 1621 HD is compatible with all 1621 standard pin box replacements, so you'll be good to go with this new kit. I've included video review of the 21K unit including a test course demo so you can get a better idea of its performance.
    view full answer...
  • Should the Air Bag on a Trailair Air Ride Pin Box Be Filled Before or After Coupling to Tow vehicle
    When using a Trailair Air Ride Pin Box, like part # LC158778 that you referenced, you should inflate the air bag to the line on the shock once it has been connected to your 5th wheel hitch. I have attached a review video where you can see this process being done at the 3:47 mark.
    view full answer...
  • Trailair Air Ride Pin Box and Shipping of Product
    The Trailair Air Ride 5th Wheel Pin Box # LC158778 is a great option for replacing Lippert 1621 and 1621 HD pin boxes. It is rated for up to 21,000 lbs and utilizes both an air bag and shock to reduce chucking and jarring on your trailer. The air bag compresses to absorb road shock and then the shock on the front of the pin box helps to bring the weight back off the air bag allowing it to rebound to absorb the next shock. I've attached a video to assist. The price for the unit can be...
    view full answer...
  • Is It Normal For Replacement Pin Box To Measure Narrower Than Brackets on Trailer
    The 11-13/16" wide measurement on the Trailair Air Ride 5th Wheel Pin Box part # LC158778 that replaces the 1621 HD pin box is standard. I was able to confirm this with the engineers at Lippert. Once you torque the bolts down the brackets on the trailer will pull in and that is completely normal. It will not put stress on the frame, replacement pin boxes are made to be a bit narrower then your brackets on the trailer so they can easily fit into place while installing. Otherwise you would...
    view full answer...
  • TrailAir Pinbox and 5th Wheel Hitch Not Level Causing Rough Ride
    If lowering the PSI on your Trailair Air Ride 5th Wheel Pin Box # LC158778 isn't working, it sounds like you need to make some height adjustments to the 5th wheel hitch, the Trailair FlexAir pinbox, or both, in order to level them out. To do this, park the truck and trailer on level ground. Using the landing gear/jacks on the 5th wheel to make it level, measure from the ground to the bottom of the pin box skid plate (not the king pin), and record the measurement. Then, measure from the...
    view full answer...
    Image 1 for
  • Is Shock of Lippert Trailair Pin Box Removable so that it Could be Painted
    The shock of the Trailair pin boxes is removable so if you wanted to remove it and then paint it you certainly could.
    view full answer...
  • TrailAir Pin Box LC158778 Installation Instructions
    I am sorry Lippert did not include their instructions with your Lippert Trailair Air Ride 5th Wheel Pin Box # LC158778 but I have included a link to them on the Lippert website. I also linked an image of page 3 from those instructions which shows the height measurement to be taken on both the original pin box and the Trailair. The torque setting for the 5/8-inch bolts is 160 ft-lbs minimum and this information appears on page 4. You are correct about the hole positions being different...
    view full answer...
    Image 1 for
  • Stabilizer Jacks Not Going Down on Winnebago Because Brakes Not Engaged
    It sounds like your 2004 Winnebago is equipped with a Lippert stabilizing jack system that requires the parking brake to be engaged on the motorhome before the jacks will operate. Before attempting to retract the jacks make sure the parking brake is set on your Winnebago. If you do have the parking brake engaged then there could be a bad connection or damaged wiring coming from the sensor on your stabilizer system. Check to make sure the connection is still good and there aren't any exposed...
    view full answer...
  • Which TrailAir Pin Box Fits 2019 Grand Design Momentum 351M
    Since your 2019 Grand Design Momentum 351M has a Lippert 1621 pin box the Trailair Pin Box part # LC158778 will fit and give you a much smoother ride! I attached a test course video link for this pin box to this page for you to check out that shows the cushioning effect in action.
    view full answer...
  • Is Rubber Plate of Trailair Rota-Flex 5th Wheel Pin Box Replaceable
    The Trailair Rota-Flex 5th Wheel Pin Box # LC158778 does not have that rubber compound as a replaceable part option from the manufacturer. I called to confirm that was the case and they said the rubber compound is built into the head. That rubber compound is designed to reduce wear and tear on the trailer by reducing road shock. It is extremely durable and I've never heard of anyone needing it replaced but older models had a different jounce style bumper that was improved upon with the...
    view full answer...
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