1. Fifth Wheel King Pin
  2. Lippert
  3. Lippert 1621HD
  4. 21000 lbs GTW
  5. Upgraded Pin Box
  6. Absorbs Road Shock and Reduces Chucking
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
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Retail:$1,662.89
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Fifth Wheel King Pin
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Shipping Weight: 184 lbs
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Lippert Lippert 1621HD Fifth Wheel King Pin - LC158778
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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. Call 800-298-1624 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 (87)
  • Q & A (264)
  • Photos
  • Why etrailer?

Lippert Fifth Wheel King Pin - LC158778

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

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

Average Customer Rating:  4.8 out of 5 stars   (87 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.

- LC158778
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


- LC158778
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!!!



- LC158778
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.



- LC158778
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.



- LC158778
by:

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



- LC158778
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



- LC158778
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.



- LC158778
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.



- LC158778
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.



- LC158778
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



- LC158778
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


- LC158778
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!



- LC158778
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


- LC158778
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.



- LC158778
by:

Very nice pin box. Did not realize it was much wider than the original 1621 pin box I had. With the slider hitch I had to rebuild the plate which adapts the hitch to the trailer.



- LC158778
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.



- LC158778
by:

Very good quality and can not wait to use the Fifth wheel this coming spring.



- LC158778
by:

Helps a lot with chuckling. Would recommend especially if you use your RV and go on long trips. Saves the driver from road exhaustion.



- LC158778
by:

Have towed over 5000 miles with the air ride hitch. No problems



- LC158778
by:

It works great on my triple tow



- LC158778
by:

Unbelievable difference from the standard king pin hitch! Made I-40 and I-70 a pleasure instead of a workout. Will definitely purchase again on the next trailer.



- LC158778
by:

It arrived in a timely matter, was able to replace the bad one, with no modifications or problems. Has worked great with about 10k miles on it already.


Comments
great, no issues, maintence free
ROBERT S - 03/14/2020



- LC158778
by:

I will not own another 5th wheel without this type of pin box. It absorbs the shock and improves the ride tremendously. It was recommended to me by a friend and I would do the same. Well built and worth every penny.



- LC158778
by:

I am pleased with the Trailair kingpin hitch. Just waiting for warmer weather to go camping.



- LC158778
by:

Very satisfied with the TrailAir. I love it so much that I went ahead and put air bags on my truck to also help. I'm looking forward to Easter for our first camping trip of 2018. Thanks for checking in.


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Show More Reviews

Ask the Experts about this Lippert Fifth Wheel King Pin

  • Is Trailair Air Ride Pin Box Compatible with Demco Hijacker Autoslide Hitch
    Trailair Air Ride 5th Wheel Pin Box # LC158778 is fully compatible with Demco Hijacker hitches such as the 18K # DM8550034 and 21K # DM8550035 which fit short beds fitted with standard above-bed base rails like Demco kit # DM8552025-71. You'll also want to use the Demco Capture Plates for Trailair Pin boxes # DM6171. Pin box part # LC158778 is a correct fit to replace a Lippert 1621HD 5th wheel pin box. This direct replacement will bolt right up in place of the 1621HD and give a smoother...
    view full answer...
    Image 1 for
  • Best Cushioned Pin Box Recommendation to Replace Roto Flex for Lippert 1621 Pin Box
    If you are looking for an improvement in ride quality over the Roto Flex you have installed on your trailer currently the best solution is the Flex Air as it cushions vertically and horizontally and the Trailair is just vertically. So for that you'd want the part # LC328492 for an 18k capacity pin box or the part # LC369535 for a 21k capacity version. The standard Trailair isn't a bad choice but if you are wanting the best option the Flex Air is the way to go. The Flex Air is also compatible...
    view full answer...
  • Availability of a Trailair Air Ride Pin Box to Replace a MorRyde Pin Box Model 1621SHD
    My contact at Lippert told me that you can replace your current MorRyde pin box with a Trailair pin box. The pin box replacement is # LC158778 Trailair Air Ride Pin Box. This pin box is rated at 21K and is the replacement for the Lippert long jaw 1621 pin box and will replace the MorRyde pin box.
    view full answer...
  • How to Determine What Pin Box is on a Trailer to Determine Which Cushioned Pin Box is Fits
    I can easily help you determine which pin box you have on your trailer. Since it is a Lippert I know we have a cushioned pin box that would work for it. But you will need to take a few measurements to know for sure. If you check out the link I attached you will see exactly how to measure your pin box to determine which you have and what cushioned pin box we offer that would fit it. The part # LC158778 would be the correct pin box to use if you have a Lippert 1621 pin box which is a very...
    view full answer...
  • TrailAir Air Ride Pin Box for a 2016 Dutchmen Voltage 3605 5th Wheel Trailer
    I did some research and it looks like the 2016 Dutchmen Voltage 3605 comes with a Tri-Glide 21K pin box but it is unclear which specific model it is. There should be a sticker on the pin box that indicates which model it is such as an L05 or some other 3 character code. It is likely based on a Lippert 1621 or 1621HD pin box which would mean that # LC158778 would be the correct replacement. To be sure I would need to know that 3 character code on the pin box. If that is not available...
    view full answer...
  • 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...
  • Determining the Pin Box of Forest River Cardinal 3825fl Trailer
    Your Forest River Cardinal 3825fl trailer most likely has the Lippert 1621 pin box. You can confirm this by looking at the pin box as there should be a sticker or stamping of a number on the actual pin box. If you cannot find the number you can use the measurements of the bolt holes of the pin box to determine which one you have. I attached an FAQ on how to do this for you to check out also. If you have the 1621 I believe you have, the Trailair Air Ride 5th Wheel Pin Box - Lippert...
    view full answer...
  • What is the Difference Between the Lippert Trailair Flex Air and Air Ride 5tth Wheel Pin Box
    The Lippert Trailair Flex Air 5th Wheel Pin Box, # LC328492, and the Trailair Air Ride 5th Wheel Pin Box, # LC158778 will both replace the Lippert 1621 pin box. Both use air spring shocks to provide for a smoother ride. The big difference between the two pin boxes will be in the towing capacity and how the hitch head is designed. The Flex Air pin box, # LC328492, has a 18K towing capacity and uses a pivoting hitch head. The pivoting head will help limit 5th wheel chucking. The head...
    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...
  • 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...
  • Difference Between Lippert 1621 Pin Box And 1621SHD Pin Box
    The difference between the 1621 and the 1621SHD is weight capacity and how many bolts is required to mount it. The 1621 uses 4 bolts for mounting. The 1621SHD requires all 6 bolts to be used.
    view full answer...
  • Can Cushioned Pin Box be Used with Andersen Ultimate Fifth Wheel Connection
    You can use a Trailair Cushioned Pin # LC158778 with an Andersen Ultimate fifth wheel adapter part # AM3200 and this would give you a much smoother ride quality which would help with wear and tear like you mentioned.
    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...
  • 5th Wheel Trailer is Too Close to Truck Cab and Tailgate on a Ford F-250
    What you will need is a Sidewinder replacement pin box that actually moves the pivot point of the trailer back 22 inches. An air ride pin box such as # LC158778 will not provide you with any additional length. To determine if there is a Sidewinder available I will need to know the manufacturer and model number of the pin box. This information should be on a sticker or plate on the pin box itself. Then you can use our Sidewinder help article, linked for you, to determine if there is...
    view full answer...
  • How Often Should Zerk Fittings On Lippert Trailair Pin Box Be Greased
    The Lippert Trailair Tri-Glide Pin Box is the only Lippert Trailair Pin Box I am aware of with grease fittings. That said, it is recommend to grease these fittings (see photo) every 1,500 - 2,000 miles. In regards to the exact amount, this is not provided as it will vary by case and how much is needed but a safe bet would be a few pumps for each fittings. The LubriMatic Mini Grease Gun Kit with Marine Corrosion Control part # L30132-11399 would be great for keeping up with the above...
    view full answer...
    Image 1 for
  • Recommended Pin Box to Reduce Chucking When Used with PullRite ISR 2400 Superlite 5th Wheel Hitch
    The 2400 ISR Superlite is not made by Reese, but rather by PullRite. You can use the Trailair Air Ride 5th Wheel Pin Box - Lippert 1621 & 1621HD - 21,000 lbs # LC158778 which will help reduce the bounce and jarring. The chucking is more front to back movement and won't be drastically improved with that combination. For your situation, I recommend the 5th Airborne Premium Fifth Wheel Air Ride Coupler - 21,000 lbs Capacity # 5AB-E1621-610 which is designed to better reduce chucking....
    view full answer...
  • Can a Trailair Pin Box be Used with a Gooseneck Adapter
    I have checked with my contacts at our gooseneck adapter manufacturers, and adapters are compatible with the traditional trail-air pin boxes. My contact further explained that this adapter is not compatible with Trail-Air's Rota-Flex pin box. This is due to the forward and rearward movement in this pin box. If you have a traditional trail-air pin box that then this adapter will work great for you. A very popular option is the Convert A Ball part # CAB-C5G which will attach to...
    view full answer...
  • What is the Correct Pin Box for a 2018 Grand Design Momentum 376TH
    According to my research, your 2018 Grand Design Momentum 376TH should use a Lippert 1621HD bolt pattern. Therefore, any of the pin boxes that are designed to replace a Lippert 1621HD should be correct for you. I have attached a list of these for you. If you are looking for a Trailair Air Ride 5th Wheel Pin Box then part # LC158778 should be correct for you. With that being said, trailer manufacturers do not provide us with information on the pin boxes they use so you will need to look...
    view full answer...
  • Replacement Pin Box Upgrade for a 5th Wheel Trailer with Venture CJ13517 Pin Box
    We have some pin box upgrades that will fit in place of your Venture CJ13517 pin box but # UF35-946208 is most like the FlexAir. It is rated for 21,000 pounds. It has 2 Urethane bumpers help to absorb road shock that do not require maintenance and a parallel linkage system that minimizes chucking. I linked an informational article on these options for you.
    view full answer...
    Image 1 for
  • How Much Air Pressure Should be in a Ultra-Fab TrailAir
    Ultra Fab has stated that usable air pressures can range from 20 to 120 psi. According to Ultra Fab there are many factors that can effect air pressure such as the size of the air spring in diameter and height, the pin weight of the trailer, the mechanics of each individual hitch, altitude and air temperature. To determine the ride height Ultra Fab has indicated on the lower body of the shock absorber, as shown on the included photo, reference points that should line up with the yellow...
    view full answer...
    Image 1 for
  • What is the Difference Between the Trailair Air Ride and Flex Air for a Lippert 1621 Pin Box
    Even though both the Trailair Air Ride # LC158778 and the Trailair Flex Air # LC369535 look similar and incorporate the air bag and shock to help improve your towing experience, the Flex Air has a few upgrades that the Air Ride does not have. The 2 things that separate these 2 5th wheel pin boxes is that the Flex Air has a rubber compound that is built into the head assembly which really helps to absorb road shock. The Flex Air also has a pivoting head which gives you controlled back...
    view full answer...
    Image 1 for Image 2 for
  • 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
  • How to Pick Out The Correct Cushioned Pin Box
    In order to pick out the correct cushioned pin box for your 2006 Alfa 30 foot Fifth Wheel trailer you will need to know which pin box model you have on your trailer. Most king pins will have the pinbox number listed on a sticker or it will be stamped on the king pin itself. If it's not there or worn out you will need to call the trailer manufacturer with the vin number of your trailer so they can provide you with that information. Check out the FAQ article I attached on cushioned pin...
    view full answer...
  • Best Pin Box Upgrade Recommendation for 2017 Grand Design Momentum with a 1621 Pin Box
    For your 2017 Grand Design Momentum that has a Lippert 1621 pin box the best upgrade we have is the Trailair Flexair part # LC328492. This has cushioning vertically and a pivoting king pin plate that allows for cushioning front to back as well. This will give you a noticeable smoother ride quality than what you currently have.
    view full answer...
  • Trailair Pinbox Fit on 2016 Forest River Cedarcreek Silverback 31RK 5th Wheel Trailer
    The Forest River website does not list the OEM pin box installed on the 2016 Cedarcreek Silverback 31RK 5th wheel, so you'll just need to take note of the pin box part number on the pin box's sticker. With that you can use the linked article to check for the correct replacement air-cushioned pin box that will bolt on in its place. The Trailair pin box you referenced, part # LC158778, is a direct replacement for the popular Lippert 1621. Another pin box that fits in place of the 1621...
    view full answer...
  • Air Ride 5th Wheel Pin Box for 5th Wheel Trailer with Lippert 1621HD Pin Box
    The Trailair and Trailair Flex Air pin boxes offer fantastic ride quality compared to standard pin boxes and would be the way I would go. But it all depends on the manufacturer and model number of your trailer's pin box. This information should be on a sticker or plate on the pin box itself. If that information is not available there are some measurements you can take to identify it. Use the help article I linked below that explains the necessary measurements if you need to. Once you...
    view full answer...
  • What PSI Should the Trailair Pin Box Air Spring Be Inflated
    The Trailair 5th Wheel Pin Boxes like # LC158778 have an air pressure range between 20 and 120 psi. The amount of air pressure needed for your specific trailer 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. It is common for the stickers to not be perfectly placed, so the manufacturer says to inflate the Air Spring # LC432404...
    view full answer...
    Image 1 for Image 2 for Image 3 for

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Info for this part was:

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