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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:$52.77
Our Price: $34.94
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Trailer Leaf Spring Suspension
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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 Redline. 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 1-636-306-4830 for expert service.
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  • Reviews (713)
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  • Videos (2)
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  • Why etrailer?

Redline Trailer Leaf Spring Suspension - APUBR-1

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

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



APUBR-1 U-Bolt Kit for 3,500-lb Round Trailer Axles





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:  4.9 out of 5 stars   (713 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:

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:

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




by:

Fit perfectly, installed today! Rides like new!




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:

Well worth it when swapping in a new axle. bought these when i got a new 3500lbs axle from E trailer as well




by:

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




by: 08/17/2022

etrailer customer service for returns and their products as a whole are third rate at best. Every product arrives damaged from terrible packaging and handling by etrailer. Customer service sometimes responds and their return policy is garbage at best. buy elsewhere




by:

I replaced the rusted out U bolts on my 5x8 utility trailer with this kit, APUBR-1 from Redline. The kit fit great, no problems. Good quality parts. Great price. Would buy from etrailer again.




by:

By far the best part of Etrailer is the online expert help! You can search existing past questions or email one of their expert to help you with your specific equipment issue, then you can select the 'correct' parts with confidence:-)




by:

Bought these to replace the original U-Bolts on my Big Tex 35SA 3500lb trailer. Arrived in 3 days and was a perfect Fit! Thank you.




by:

I was stranded in the middle of no where with a broken spring up a rough mountain road. I was able to overnight these parts to a nearby town hardware store (who i asked in advance) and back on the road within 3 days. ETrailer answered all my questions and was very helpful to get these parts expedited. Thank you!




by:

Received parts in a timely manner are are of great quality. Parts installed as they should with no issues.




by:

The best technical support, the best communication, and the best service of any retailers I’ve done business with. Order with confidence.




by:

My boat trailer suspension repairs were made easy by your well designed website with complete descriptions and your prompt delivery of the correct, much better than the original equipment parts. I could have had a couple more weeks of fishing had I found you sooner. Thanks.




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:

Not home yet but the wife said it's at the house... thanks etrailer..




by:

Easy to install




by:

Joann was very knowledgeable and very helpful.. my trailer axle and parts arrived on time and everything was in order..it doesn’t get any easier..




by:

Your website was easy to navigate to the items I needed. The price was good and shipping was quick. Thank you.




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!!!




by:

Number one quality parts. Had to replace the axle due to lack of lubrication of the wheel bearings. Love the concept and ease of keeping the wheel bearings supplied with fresh grease on the e-z lube axles.




by:

Good product easy install comes with all hardware.




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:

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:

Fit perfectly for my trailer. All the components seem to be heavy duty.


Comments
Well, its been a year and I am still very impressed with the suspension parts I got from eTrailer. I have ran my car trailer from Michigan down to southern Ohio, Indiana, and Illinois. Had no issues what so ever. The trailer handled beautifully.
Sgtbass64 - 12/09/2016

25
713
Show More Reviews

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    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...
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    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.
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