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U-Bolt Kit for Mounting 3,500-lb, Round Trailer Axles - 5-1/2" Long U-Bolts

U-Bolt Kit for Mounting 3,500-lb, Round Trailer Axles - 5-1/2" Long U-Bolts

Item # APUBR-1
Retail:$74.28
Our Price: $50.48
You Save: 32%
Trailer Leaf Spring Suspension
Shipping Weight: 5 lbs
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Mount your round, 2-3/8" diameter axle to your trailer's leaf springs with this U-bolt kit. U-bolts, plates and nuts included. Great Prices for the best trailer leaf spring suspension from Dexter. U-Bolt Kit for Mounting 3,500-lb, Round Trailer Axles - 5-1/2" Long U-Bolts part number APUBR-1 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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  • Reviews (821)
  • Q & A (0)
  • Videos (2)
  • Photos

Dexter Trailer Leaf Spring Suspension - APUBR-1

  • U-Bolt Kits
  • Camper
  • Car Hauler
  • Utility Trailer
  • Round Axle - 2-3/8 Inch
  • 5-1/2 Inch Long
  • 3500 lbs
  • 1/2 Inch Diameter
  • Dexter

Mount your round, 2-3/8" diameter axle to your trailer's leaf springs with this U-bolt kit. U-bolts, plates and nuts included.


Features:

  • Attaches trailer axle to leaf springs
  • Includes:
    • (4) 5-1/2" Long U-bolts (176400)
    • (2) U-Bolt plates for 1-3/4" springs (117595)
    • (8) 1/2"-20 Hex nuts (12N)
  • Spring seats required for mounting axle to leaf spring sold separately


Specs:

  • Axle diameter: 2-3/8"
    • Typical 3,500-lb axle
  • Spring width: 1-3/4"
  • Dimensions: see below


U-Bolt Diagram



K71-731-00 U-Bolt Kit for 3,500-lb Round Trailer Axles

Replaces APUBR-1





Video of U-Bolt Kit for Mounting 3,500-lb, Round Trailer Axles - 5-1/2" Long U-Bolts

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for Trailer Axle Long U-Bolt Mounting Kit Review

Speaker 1: Today we're going to be taking a look at the Redline U-bolt kit for mounting 3500 pound round trailer axles. These are 5 1/2 inch long U-bolts. The part number is APUBR-1.Now, when replacing your axle, it's a really good idea to also replace the U-bolts. These are a pretty cost effective item you can get and ensure that you're going to have excellent, excellent hold with your axle to your springs. You can see this is going on a floor spring pack. The opening on them is going to be 2 3/8 inch, so it's going to fit the outer tube diameter of our axle here.

It comes with the new lower plate, and also four new flange nuts that allows you to secure that end, keep everything locked tight, so you don't have any issues for a very long time.Now we're going to remove the four nuts on the bottom here that hold our axle down, and they hold the U-bolts here. When replacing an axle, generally you're going to replace these as well, just because these can kind of stretch over time. So, if these nuts won't come off, you can also just cut your U-bolts on each side.Now we're going to grab our new U-bolt kit and place these down and around, just like our old U-bolts were, and when we we'll replace the bottom bracket up on the U-bolts we'll see the hole here in the middle. That's meant for that nut to come down through, and then in each position we'll install one of the flange nuts.Now we'll go through and you're evenly going to tighten down our bolt. We'll get them snugged up first and then we can torque them.

For these nuts you'll want to use a 19 millimeter 3/4 inch socket. Notice we're tightening them evenly, but in a crossing pattern.That's going to compete our look at the U-bolt mounting kit for 3500 pound round trailer axles, part number APUBR-1.

Customer Satisfaction Score:


Customer Reviews

U-Bolt Kit for Mounting 3,500-lb, Round Trailer Axles - 5-1/2" Long U-Bolts - APUBR-1

Average Customer Rating:  4.8 out of 5 stars   (821 Customer Reviews)

Mount your round, 2-3/8" diameter axle to your trailer's leaf springs with this U-bolt kit. U-bolts, plates and nuts included.

by:

It is exactly as described. It seems solid. I also ordered the springs, and they appear to be solid as well. I look forward to continuing to do business with etrailer due to quality parts AND great customer service from the likes of Shawnee and the crew. Thank you!!!

Bill

12/6/2023

It’s been a year and the trailer is as good as new. The leaf springs have held up well after many trips across the desert several miles of unpacked road and into town 80 miles one way to haul in materials cinder block, Portland cement, etc to finish building my house. Just bringing an empty load across these roads is abusive to any trailer, but many, many full loads later and the trailer is doing great! Thank YOU!



by:

STEEL PLATES WERE DRILL BUT NOT ROLLED/FORMED LIKE ORIGINALS. PLATES STARTED TO BEND BEFORE REACHING 60 FT LBS. ORDERED ON JUNE 8TH DID NOT RECEIVE UNTIL JUNE 2OTH. VERY UNIMPRESSED!



by:

I recently replaced my 1/2 ton truck with a 3/4 ton truck. In order to hook up to my existing fifth wheel camper, I had to raise my camper. To do this, my brother and I moved the axles from the top of the leaf springs and attached them under the springs. This kit made it very easy to do this. We torched off the old u bolts and used this set as a replacement. The quality of this kit was very good. Hard to get too excited about u bolts but I would purchase this again if I had to do it all over again.

I was able to gain about 5 1/2 inches by flipping the axles. Here is a before and after.



by:

This set of leaf springs was excellent choice for my 4’x8’ utility trailer, handles great.



by:

Everything worked great---All the correct parts ---the best place to buy parts.
very good service thanks to James. YEA

Janet L.

12/3/2023

working great no problems!

Etrailer Expert

Mike L.

12/3/2023

@JanetL We're glad to hear that!


by:

etrailer always has what I need in stock. And the parts are high quality. Plus their professionals always have sound advice and recommendations for me. They are a one stop shop! Than You etrailer!!



by:

The order was shipped like the day after it was placed. Everything seems to be high quality. There was even a color brochure that described the entire installation. Even though I was the distinguished honor graduate from my Alma Mater (Real Men Don't Need Instructions) I did read the pamphlet and found the instructions and tips to be very helpful.



by:

This was used to replace original factory parts that were completely worn out. I am extremely happy with the parts I received. Everything worked like it was supposed too



by:

These did not fit my 3500 lb axle. It has been very difficult determining the correct size U-Bolts for my axle. It appears etrailer does not carry the size I need.

Etrailer Expert

Jenny N.

2/6/2024

It is true that we do not carry all sizes of u-bolts. The best way to determine what you need to take a few measurements. First, you want to check to see if you have a round versus square axle. Second, using your old u bolt, measure the width on the inside of the u bolt [between the bolt arms]; this will match the width or diameter of the axle. Secondly measure the length of the bolt arm. This depends on the axle diameter and number of leaves on springs. The u-bolts must be long enough to clear the axle, spring seat, and springs. Last, you want to measure the diameter of the bolt arm. Please see the FAQs below, one for double eye trailer suspension and one for slipper spring suspension that will go into more detail.



by:

I was shorted to you, Walts I called customer service. They immediately took care of it and shipped me out a new product. I’ve got to admit the quality of the product is great and the customer service is even better. Thank you E-trailer .



by:

Purchased several axle and suspension/mounting parts from etrailer. Parts are always of good quality and work well. Shipping times are always reasonable. Plan to continue using them as a supplier for my trailer parts.



by:

The kit was perfect to replace my original equipment on my 2007 trailer.



by:

Easy installation and have worked just fine every since.



by:

These axle u-bolt mounting kit worked great and did exactly what it was supposed to do. Install was easy and it contained the parts that I needed.



by:

replaced my old axle and hubs with a heavy duty axle, U-bolts and new hubs. It has all held up well. I had to custom weld the axle carrier to fit my trailer, but everything fit well, and was a fairly easy installation. I now feel much more confident with a 3500 lb. axle and these heavy duty U bolts under my trailer.



by:

Last project built. Used etrailer for almost all parts, 7 pin wiring harnesses, junction block, tail lights, jacks, spring retainer bolts vent cover and so on. Love the leveling jacks. Friend wants one now so started another one. I will be getting all the parts from etrailer...



by:

The springs were a perfect match up. Easy installation with the exception of my existing rusted bolts Prompt service, exact replacements would not hesitate to use etrailer for any parts for my three trailers



by:

Parts fit as advertised, very satisfied with purchase. I new nothing about replacing a trailer axle info on web site and support provided were excellent.
Definitely would recommend etrailer



by:

I am building my daughter and snl a kayak trailer so i ordered some new ubolts and plates. fit like a glove. Etrailer has what i9 want every time.



by:

Your gonna need new u-bolts when replacing springs. Cut the old ones off, use these to bolt it back together. Easy to install



by:

Ups brought the package within 18 miles of my house and then handed it off to the usps which delayed the package was going on trip Monday but can’t because the shipment got here later and also the unbolts are not galvanized or show what grade medal they are not good

Etrailer Expert

Jenny N.

4/4/2023

These u bolts are made of steel and the parts have a raw finish. The are covered with a light layer of oil to help protect against corrosion during storage.



by:

I replaced a bent axle. This u-bolt kit made the whole replacement a snap! A perfect fit.



by:

Super fast shipping and exactly what we needed!



by:

Great customer service. Did not receive all of items on the first try,but when I called and explained they had the rest sent right away!Everything looks good to go.



by:

It was so nice to work with new and proper fitting mounting bolts. Everything I needed to attach the axles was in the kit.


25
821
Show More Reviews

See what our Experts say about this Dexter Trailer Leaf Spring Suspension

  • Longest 1/2' U-Bolts Available for 3,500 Lb Round Axle
    The longest u-bolts we currently offer in 1/2" for a 2-3/8" diameter axle is 5-1/2" such as the U-Bolt Kit part # APUBR-1.
    view full answer...
  • Kit Needed to Move Trailer Leaf Springs Back Under Axle
    If the leaf springs for your trailer are currently installed so that they are sitting on top of the axle, you can just use a standard U-Bolt Kit to move the leaf springs back under the axle. For a 2-3/8 inch, 3,500 pound axle, you will need the Redline U-Bolt Kit # APUBR-1 and for 3 inch axles with 5,200-7,000 pound capacities, you will use # APUBR-8. I have also attached a helpful installation video for you to check out.
    view full answer...
  • U-Bolt Mounting Kit For A 1,500 Pound Round 1-3/4 Inch Axle
    The U-Bolt Kit for Mounting 2,000-lb, Round Trailer Axles # APUBR-10 is the correct kit for you. This kit includes 4 U-Bolts, 2 U-Bolt Plate and the hex nuts needed to install to your axle. I attached a review video link below.
    view full answer...
  • Torque Specs for U-Bolts on 3,500 Pound Axles
    For 3,500 pound axle U-bolt kits like the Redline # APUBR-1 that use 1/2 inch hex nuts you will want to torque them down somewhere between 45 and 70 foot pounds. I have attached a great article on trailer suspension that includes this info along with details on all the other necessary components that you can look through.
    view full answer...
  • Choosing a U-bolt Kit for Trailer with 1-3/4 Inch Wide Leaf Springs
    When choosing a U-bolt kit for you trailer, you want to choose the correct kit based on the size of your trailer's axle. The width of the leaf springs isn't the main factor. The U-bolt kits you referenced will not both work on the same trailer axle. The # APUBR-8 kit can accommodate both 1-3/4 inch and 2 inch wide springs, but it is designed for use on 3 inch diameter round trailer axles that have capacities between 5,200 pounds - 7,000 pounds. The # APUBR-1 kit will accommodate 1-3/4...
    view full answer...
  • What is the Torque Rating for 1/2 Inch U-Bolts for Leaf Spring Trailer Suspension
    The torque rating for 1/2 inch u-bolts in U-Bolt Kit, # APUBR-1, is a minimum of 45 ft lbs and a maximum of 70 ft lbs.
    view full answer...
  • U-Bolt Kit Recommendation for 3,500 lb Trailer Axle that is 2-3/8 inch In Diameter
    The part # APUBR-1 is available through us. It is a U-bolt kit for 3,500 lb axles like what you have which are rated for 3,500 lbs.
    view full answer...
  • Castle Nut Torque Spec for 3,500 Pound Axle
    It sounds like you're asking about the torque spec for the castle nut on your 3,500 lb axle. There is no specific torque rating when installing the castle nut on any axle. You want to run the nut down until there is no side to side play in the hub, and then back it off to the next notch in the castle nut so the retainer can secure the nut. Over-tightening the castle nut can damage the bearings, races and spindle. I have attached a video showing this process. If you jump to the 4:45 minute...
    view full answer...
  • Can the U-Bolts of the U-Bolt Kit # APUBR-1 be Cut 1/2 inch Shorter
    We can't cut the U-bolts of the U-Bolt Kit # APUBR-1 1/2 inch shorter. But you certainly can if you have a grinder or know someone who does. It would be pretty easy to do, especially if you have a cutting wheel.
    view full answer...
  • Grade of U-Bolt in the U-Bolt Kit APUBR-1
    The U-bolts of the U-Bolt Kit part # APUBR-1 are Grade 5. I attached an install and review video for this kit for you to check out as well.
    view full answer...
  • Are U-Bolts Includes with Trailer Axle
    The trailer axles we currently have available do not include the U-bolts necessary to mount the axle to the leaf springs on your trailer. The U-bolts you need will depend on the size of axle you are purchasing, along with its capacity. I have attached a couple links that will take you to our available selection of trailer axles and U-bolt kits that you can look through. If you can tell me what type of axle you are getting, I will be happy to recommend a kit that should work nicely.
    view full answer...
  • Longest U-Bolt Kit for Trailer Axles that are 2-3/8 inches in Diameter
    The inner width of the U-bolt needs to match the diameter of the axle that you have. The longest kit we have that has a 1/2 inch diameter studs is the part # APUBR-1 which has U-bolts that are 5-1/2 inches long.
    view full answer...
  • Finish of Redline U-Bolt Kit # APUBR-1
    The # APUBR-1 U-bolts are constructed of steel, and the parts have a raw finish. They are coated with a light film of oil to help inhibit corrosion during storage.
    view full answer...
  • What Grade is the U-Bolt of the U-Bolt Kit part # APUBR-1
    The U-bolts of the U-Bolt Kit part # APUBR-1 are Grade 5. The torque range is minimum of 45 ft lbs and a maximum of 70 ft lbs. I attached an install and review video for this kit for you to check out as well.
    view full answer...
  • Should I Replace the U-bolts When Replacing the Leaf Springs
    I would not recommend reusing your existing u-bolts because the nuts are designed to mis-align the threads as they are tightened down to prevent the u-bolts from coming loose. You should choose the u-bolt kit that will fit the diameter of your axle. The u-bolt kit # APUBR-1 that you referenced is designed for one 3,500 lb trailer axle with a diameter of 2-3/8 inches. The kit includes 4 u-bolts, 2 u-bolt plates and 8 hex nuts 1/2 inch.
    view full answer...
  • Torque Specs for U-Bolts on LoadRite Boat Trailer
    The correct torque spec for trailer suspension u-bolts will depend on the the diameter of the bolt. You will want to use the following depending on bolt size: 1/2" bolts: 45 ft/lbs - 70 ft/lbs 9/16" bolts: 65 ft/lbs - 95 ft/lbs 5/8" bolts: 100 ft/lbs - 120 ft/lbs 3/4" bolts: 140 ft/lbs - 160 ft/lbs The U-Bolt Kit part # APUBR-1 that you were referencing will need to be torqued to 45 ft/lbs - 70 ft/lbs as they are 1/2" diameter bolts. There should not be any space between the u-bolt plate...
    view full answer...
  • Torque Specifications for Redline U-Bolt Kit APUBR-1
    The torque rating for the 1/2 inch diameter u-bolts in the U-Bolt Kit # APUBR-1 is a minimum of 45 ft lbs and a maximum of 70 ft lbs. These are designed to mount your trailer's leaf springs to round, 2-3/8 inch diameter axles. The U-bolts, plates and nuts are all included in this kit. I have attached a couple of videos on this product so you can look at the installation process and see exactly what all is included in the kit.
    view full answer...
  • Parts Needed to Add Replacement Axles to Tandem Axle Trailer
    We do sell replacement trailer axles. To see if what we have would work for you, I'd need some information from you. I'll need the following: - Hub face to hub face dimension -Spring center to spring center dimension - Axle capacity - Reference numbers from inner and outer wheel bearings With this information, I'd be able to check to see if one of our axles would work for you.
    view full answer...
    Image 1 for
  • Installation of the U-Bolt Kit for Mounting 3500 lb Round Trailer Axles
    The U-Bolt Kit for Mounting 3,500-lb, Round Trailer Axles - 5-1/2" Long U-Bolts # APUBR-1 do not have a specified torque from the manufacturer. I did some research online and it appears that about 72 ft lbs would be appropriate for the 1/2 inch diameter nuts on the U-bolts.
    view full answer...
  • Torque Specifications on Lug Nuts, Leaf Springs, and Equalizers.
    For U-bolts like # APUBR-1 the torque spec is between 45 and 75 ft-lbs. For the shackle bolts on the end of your leaf springs and a standard equalizer there are no listed torque specs. If you make them too tight they won't function properly. I would tighten them down until they make contact with your shackle straps and then add another 1/4 turn. For the torque spec on the lug nuts on your wheels see the chart below.
    view full answer...
    Image 1 for
  • Replacement Axle for 1993 Western World Tandem Axle Trailer
    We do sell some replacement trailer axles. To see if what we have would work for you, I'd need some information from you. I'll need the following: Hub face to hub face dimension Spring center to spring center dimension Axle capacity Reference numbers from inner and outer wheel bearings With this information, I'd be able to check to see if one of our axles would work for you.
    view full answer...
    Image 1 for
  • Can a Three Leaf Spring Stack Be Used To Replace a Two Leaf Spring Stack
    Yes, you can replace a two leaf spring stack with a three leaf spring stack so long as your center to center (double eye springs only) measurement matches but please note the loaded and unloaded as well as the new and used center to center measurements will be different. There is a correlation between the numbers of leaves in a stack and the weight capacity of that stack but there are also two leaf spring stacks with the same weight capacity as three leaf spring stacks so going by the rated...
    view full answer...
  • Recommended U-Bolt Mounting Hardware for 3,500 lb Axles
    It sounds like you have 3,500 lb axles that are typically 2-3/8 inch diameter and could easily be rounded up to 2.5 inches. For your U-bolts, I recommend the CE Smith U-Bolt Kit- Zinc # CE230025 for the increased corrosion resistance or the U-Bolt Kit # APUBR-1 for basic mounting kit. I've attached some videos to assist.
    view full answer...
  • U-Bolt Kit for Dexter 3,500 lb. Round Trailer Axle Beams
    For a 2-3/8 inch diameter round trailer axle such as # 8327812-I you will need u-bolt kit # APUBR-1. It includes 4 u-bolts, 8 nuts, and 2 u-bolt plates. I have included a link to a video featuring this kit for you. The spring seats are already welded to the axle.
    view full answer...

Do you have a question about this Trailer Leaf Spring Suspension?


Info for this part was:

Employee Mike L
Expert Research:
Mike L
Employee Michael H
Expert Research:
Michael H
Employee Jameson C
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Jameson C
Employee John H
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John H
Employee Adam R
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Adam R
Employee Kathleen M
Video by:
Kathleen M
Employee Zach D
Video by:
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Employee Cole B
Installed by:
Cole B
Employee Randy B
Installed by:
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Employee Andy C
Installed by:
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Employee Chad S
Video Edited:
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Employee Chris R
Video Edited:
Chris R
Employee Wilson B
Updated by:
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Employee Alexander C
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