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U-Bolt Kit for Mounting 5,200-lb to 7,000-lb, Round Trailer Axles - 7" Long U-Bolts

U-Bolt Kit for Mounting 5,200-lb to 7,000-lb, Round Trailer Axles - 7" Long U-Bolts

Item # APUBR-8
Retail:$61.50
Our Price: $44.74
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Trailer Leaf Spring Suspension
Shipping Weight: 6 lbs
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Mount your round, 3" 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 5,200-lb to 7,000-lb, Round Trailer Axles - 7" Long U-Bolts part number APUBR-8 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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  • Reviews (329)
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  • Videos (1)
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Dexter Trailer Leaf Spring Suspension - APUBR-8

  • U-Bolt Kits
  • Camper
  • Car Hauler
  • Utility Trailer
  • Round Axle - 3 Inch
  • 7 Inch Long
  • 5200 lbs - 7000 lbs
  • 1/2 Inch Diameter
  • Dexter

Mount your round, 3" 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) 7" Long U-bolts (1755892)
    • (2) U-Bolt plates for 1-3/4" or 2" springs (117521)
    • (8) 1/2"-20 Hex nuts (12N)
  • Spring seats required for mounting axle to leaf spring sold separately


Specs:

  • Axle diameter: 3"
    • Typical 5,200-lb to 7,000-lb axle
  • Spring width: 1-3/4" or 2"
  • Thread dimensions: 2" long x 1/2"-20
  • Dimensions: see below


U-Bolt Diagram



K71-732-00 U-Bolt Kit for 5,200-lb to 7,000-lb Round Trailer Axles

Replaces APUBR-8





Video of U-Bolt Kit for Mounting 5,200-lb to 7,000-lb, Round Trailer Axles - 7" Long U-Bolts

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




Video Transcript for Review of Dexter Trailer Leaf Spring Suspension - U Bolt Kit 5200 7000 lb Round Axle - APUBR-8

Hi, everybody, Andy here with etrailer.com. Let's take a look together at this Dexter U-Bolt Kit for mounting 5,200 to 7,000-pound round trailer axles. Now this kit is designed to fit axle diameters of three inches, which is going to be your typical 5,200 to 7,000-pound axles. And this kit includes everything that you see here on my table before me. You're going to receive four seven-inch long U-bolts and then two U-bolt plates for 1 3/4-inch or two-inch springs, and then eight 1/2 inch by 20 nuts. And the spring seats.

Spring seats are required for mounting the axle to the leaf springs, and those are gonna be sold separately from this kit. Now, if we measure from the inside of the U-bolt to the bottom of the bolt post, that's gonna give us our seven-inch measurement. And these are tapered where the axle sits to help the U-bolt stay in place on your axle. And the area between the bolt post measure three inches. So that's where we are...

That's where we get the spring width fitting from. And then the diameter of each one of these bolts measure half an inch. And of course, the plates that are included are designed to fit these U-bolts. Well, that's gonna wrap up our look today. I do hope that it was helpful for you.

Again, my name is Andy, thank you for joining me.

Customer Satisfaction Score:


Customer Reviews

U-Bolt Kit for Mounting 5,200-lb to 7,000-lb, Round Trailer Axles - 7" Long U-Bolts - APUBR-8

Average Customer Rating:  4.8 out of 5 stars   (329 Customer Reviews)

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

by:

I upgraded my leaf springs to 4000lbs springs and needed longer axle U bolts and Quinn at etrailer was helpful getting the correct bolts headed my way.



by:

These seem to be working ok but do not appear to be designed for use with the HD upgraded Moryde greaseable shackle kit that I purchased with them . You can see in the photos that they rub and bind

Etrailer Expert

Jenny N.

4/22/2022

I do have two recommendations for you. The first would be to make sure that the bolts are not over tightened. The locknuts should only be tight enough to limit as much movement as possible without binding anything up. The second recommendation is that Lippert makes that can be used with the Equa-Flex system. It is part # LC64FR. The shackle straps are less thick at 0.212 thickness however they are longer at 3 and one quarter inches.



by:

Excellent product, I used it to beef up the suspension on my welding trailer. It has proven to be a great quality product. Even though local stores carry this kit, I trust a company with the word trailer in its name, and for good reason. I recommend your website to all of my welding students, so if you're ever in the mood to send parts for me to install, test, and review. Please keep me in mind. I'm currently searching for a good 10" electric brake assembly to replace my existing set, and I'm sure I will be reaching out to etrailer for their expertise.



by:

The u-bolts fit and worked perfectly. I didn’t use the included tie plates, my travel trailer has shock absorbers that attach to the tie plates, I reused the originals. I torqued them to 70 ft. lbs. per Dexter axle specifications. I did clean and paint them before installing. I upgraded my 5400 lb. 4-leaf springs to 6000 lb. 5-leaf springs, which required longer u-bolts.



by:

Working great. Still doing well after a year of full time travel on a 5th wheel RV.



by:

Wow! I have ordered from etrailer for years. Great products. I ordered this on a Tuesday and received it Thursday and shipping was Free!
Painting them now to match trailer and installing them tomorrow. All within a week. Like I said, Wow!



by:

Just installed them a few minutes ago. Great product. I liked the extra ribs in the bottom mounting plates. It seemed to add a great deal of strength. I thought the shipping was a little steep but all in all a good experience. Thank you.



by:

Everything fit together perfectly. Had a few more nuts in the box than I needed but that is better than being short! :-)



by:

these u bolts and brackets arrived quickly, installed flawlessly, and seemed to be heavy duty.
i couldn't be happier.



by:

A+ works great. Fast shipping if I ever need axle again will buy from you



by:

Quality product. Works perfectly on my 1968 Plymouth leaf springs.



by:

I will always order my trailer parts from this company they were quality and reliable I've had a lot of cars using their equipment and parts keep up the good work



by:

Nice Robust suspension parts. I'm however using these for Ham radio antenna Mounts, as i can't find u bolts in this size in the Ham world... Cheers..



by:

I think you screwed up. I did not receive the U bolt kit, I received Part # CT-3000-RK, Repair kit for 2" straight coupler which I did not order. I reported this upon delivery of the wrong part.

Etrailer Expert

Jenny N.

7/21/2022

We recently sent you a new u bolt kit and were wondering if you had any feedback about the product for other shoppers? We look forward to hearing from you.



by:

I like the fitment of them. The ease of nutting the u bolt was great. The serrated flange nuts probably won't back off, but I like overkill. I will double nut then due to I think road vibration will loosen them.

Dominic

2/20/2018

After a year it works flawlessly as expected.



by:

I pull a toy-hauler 5th wheel trailer between Alaska and the lower 48 through Canada twice a year. Much of the road is rough and caused me to break a leaf spring every trip. Since installing a shock absorber system and upgrading from 5-leaf to 6-leaf springs, I have so far eliminated suspension damages on the route.



by:

It was just what I needed for my project. I am converting an old surplus army trailer to a more useful utility trailer. That included changing the axel to lower the higher of the trailer. The axel I had was an old mobile home axel that I shortened. The diameter was smaller than the existing axel and the u bolts were to big. These worked perfect after I modified the mounting plates. Thanks again. I will be using you all again on my next project.



by:

Good value and perfect fit.



by:

Super fast service, arrived 4 days early. Packaging was pretty bad but the parts made it and worked great



by:

Excellent people to work with.
I received
what I ordered, and in two business days.

Only problem, was I ordered the wrong size leaf springs and U-bolts.
But, returned them, no problems. Full refund, minus return shipping.
Also, re-ordered. Hopefully, the correct size, this time. (I was three hours away from my trailer the first time I ordered)

Robert H.

10/17/2018

Second time was a charm! Good product. Fit perfectly. Thank you!



by:

Perfect for my application



by:

Product was exactly what I needed and got here pretty quick.



by:

Wanted to switch to five leaf springs from 4 leaf on my dual axle 27 ft. trailer. Prices were better than I could get in Calif. with addition of free shipping. Parts arrived in three business days, I was surprised at promptness. Staff very helpful after I got my measurements figured out, as old springs were stretched 3/8 inch. Shocks arrived just after I had the springs all installed. Parts were great, only thing I would have liked better was a small instruction sheet on torqueing bolts. Would recommend etrailer to my friends.



by:

Have not installed them yet but they look very good. Heavy duty as expected. One u-bolt is a bit twisted fresh out of the box but it should be easy to correct using a vise. Only one of the 8 I bought was this way. Must have slipped past quality control at the factory. It will not affect its integrity or usage.

Dave L.

8/28/2021

The kit is working great. No problems with it. Many thousands of miles since the install.



by:

Just what I needed to complete my stock trailer repairs


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Show More Reviews

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

  • Should the Tie-Plate Bend When Tightening Axle U-Bolts
    The recommended torque for a 1/2" diameter u-bolt like the U-Bolt Kit for Mounting 5,200-lb to 7,000-lb, Round Trailer Axles part # APUBR-8 is between 45 and 70 ft lbs. If you are having issues with the tie-plates distorting at 65 ft lbs then I recommend going with a torque setting on the lower end of the above scale. If the tie-plate becomes distorted too much this can weaken the metal but only slight distortion should not be too much of an issue.
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  • Can 3,500 lb Axle be Upgraded to 5,200 lb Axle
    I don't see any issues with running a heftier 5,200 lb trailer axle with leaf springs rated for 3,500 lbs as long as you're mindful of any changes that might need to take place like a longer U-Bolt Kit like part # APUBR-8 and larger tires/wheels as the hubs that fit the larger axle capacity have a 6 on 5-1/2" bolt pattern while your current setup likely has a 5 on 4-1/2" bolt pattern. This also means you'll need to make sure you still have 4" of height clearance from your tires to the...
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  • 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.
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  • 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...
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  • How to find the correct replacement trailer axle for overslung setup
    The Dexter Trailer Axle Beam with E-Z Lube Spindles - 86-1/2" Long - 5,200 lbs # 8327816 is the closest option available. The hub face to hub face measurement is only 1-1/2" more than your current setup, which won't cause any issues. The main thing to look at and match up EXACTLY is the spring seat to spring seat spacing. Since you need 68-1/2" spacing, and this axle provides 71-1/2" spacing, you will need to cut the spring seats off and move them to the appropriate spot for your trailer...
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  • How to Determine Correct U-Bolt Kit and Leaf Spring Bushing for a 6,000 Lb Trailer Axle
    A 6,000 lb axle is usually going to be 3" in diameter. Therefore, for the u-bolts you can use part # APUBR-8 for 7" long or part # APUBR-9 for 7-1/4" long. You can measure your existing u-bolts or from the bottom of the axle to the top of the leaf spring pack in order to determine which length you need. You can always choose the longer option and cut away any remaining threads if necessary. Most leaf springs for 6,000 lb axles are 1-3/4" wide and will use a 9/16" bolt. If this is the case...
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  • Do The Trailer Suspension Hangers & Equalizers Need To Be Changed Going From 3,500 to 6,000LB Axles?
    You may be able to use the same hangers and equalizers that are already being used on your triple axle trailer. First you will need to determine if you will be changing wheel and tire sizes that will require you to move the axles further apart so that the tires do not contact each other. This may also affect your trailer fenders if the axles are being spread further. If your tire spacing is okay you will then only need to find the larger capacity leaf springs that match the length of...
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  • Distance From Inside Arc Area Of U-Bolt To Threads For U-Bolt Kit Mounting Kit
    I pulled one of the U-bolts we offer from our warehouse and took a quick measurement for you. The distance from the inside of the inside arced area of the U-bolt, part # CE23003 to the threads on the leg is 4-3/4 inches. The threaded portion is 2 inches. I also pulled another set of U-bolts, part # APUBR-8 and the measurement from the inside of the arc to the threads is the same 4-3/4 inches as well as the threaded portion being 2 inches. This is a 1/2-20 fine thread U-bolt.
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    Image 1 for
  • Replacement 24-7/8" Long Leaf Springs for 5,000 Pound Axles
    To replace your existing leaf springs the 6-Leaf Double-Eye Spring # SP-222275 will work perfectly. This leaf spring stack measures right at 24-7/8" from eye to eye (center to center) and its designed for 5,300 pound axles (which will work without issue on your 5,000 pound units). For a U-bolt kit I recommend the Redline # APUBR-8, which includes four 7" long U-bolts, two U-bolt plates, and the needed 1/2"-20 hex nuts. I have attached a couple short video reviews on these products below...
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  • Torque Specs For U-Bolt Kit part # APUBR-8
    For the 1/2 inch u-bolts in U-Bolt Kit for Mounting 5,200-lb to 7,000-lb, Round Trailer Axles - 7" Long U-Bolts Item # APUBR-8 torque the nuts to 70 foot pounds each. If you need a torque wrench we have # ALL944001 good for 10 to 150 foot pounds and it has both a 3/8 inch drive and 1/2 inch drive.
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  • Does the Dexter 7K Trailer Axle with Electric Brakes Come Assemblied
    The Dexter Trailer Axle w/ Electric Brakes part # 8327864-EB does come with the hubs and backing plates already installed so you would be ready to go once it arrives. It however does not come with u-bolts so if you need those as well you can obtain the U-Bolt Kit for Mounting 5,200-lb to 7,000-lb, Round Trailer Axles part # APUBR-8.
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  • What is the Torque Spec for 1/2 Inch Axle/Suspension U-Bolts on 5200 Pound Trailer Axle
    On the 1/2 inch u-bolts in U-Bolt Kit for Mounting 5,200-lb to 7,000-lb, Round Trailer Axles - 7" Long U-Bolts Item # APUBR-8 torque the nuts to 70 foot pounds each. If you need a torque wrench we have # ALL944001 good for 10 to 150 foot pounds and it has both a 3/8 inch drive and 1/2 inch drive.
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  • Recommended Tandem Axle Trailer Hanger Kit for 40 Foot Trailer
    Yes, the length of the trailer frame will play a part in determining where to position the trailer axles. The axles will need to be placed under the trailer so that 10-15% of the total weight will be on the tongue. I have attached a photo below with the formula you will need to use in order to find out the best spot to place your axles. In regards to parts needed for the above, I recommend the Tandem-Axle Trailer Hanger Kit for Double Eye Springs part # APT5 with the U-Bolt Kit for Mounting...
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  • Torque Needed to Tighten Nuts of 3 inch Trailer Axle
    The torque needed to tighten the U-bolts of a trailer's 3 inch axle like the # APUBR-8 is 70 ft lbs. If you need a torque wrench we have # ALL944001 good for 10 to 150 foot pounds and it has both a 3/8 inch drive and 1/2 inch drive.
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  • Recommended Slipper Spring And U-Bolt Kit For Trailer With 7,000 Lb Axle
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    Image 1 for
  • Correct U-Bolts For 3,500Lb Dexter Axle
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  • Correct Replacement Leaf Springs for Grand Design 28BH
    The 5-Leaf Double-Eye Spring part # e34SR will be a great fit for a Grand Design 28BH with Dexter 5,200 Lb Axles and it offers a bit higher capacity than standard so you'll get more support and life out of the springs. They will be a direct bolt-on fit and replacement. Please note, new springs are shorter than the old ones as the older ones stretch. For a new u-bolt kit, you'll need the U-Bolt Kit for Mounting 5,200-lb to 7,000-lb, Round Trailer Axles part # APUBR-8.
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  • Can 26" Double-Eye Leaf springs Replace 25-1/2" Double-Eye Leaf Springs
    Hi Tim, A half inch difference between your old springs and some new springs would be well within tolerance so you would not need to replace the equalizer. The equalizer end of the # e27SR will sit slightly more in towards to the center hanger but it's such a small amount that it won't make a huge difference. You will want to replace the U-bolts when swapping out the leaf springs since they get stretched when torqued down and shouldn't be reused. With you having a 4,400lb axle it should...
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  • Heavier Duty Leaf Springs To Replace Dexter 072-097-00 On 2018 Keystone Cougar 311RES 5th Wheel
    I would be happy to help! Since your 2018 Keystone Cougar 311 RES 5th wheel with tandem 5200lb Dexter axles has the Dexter 072-097-00 leaf springs currently installed the 5-Leaf Double-Eye Spring for 6,000-lb Trailer Axles - 25-1/4" Long # e34SR you were looking at will be an exact replacement for you. These leaf spring are the same length at 25-1/4" and the 6000lb capacity of the # e34SR will give you the extra support you are looking for. For replacement U-Bolts I recommend four of...
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    Image 1 for
  • Replacement Double Eye Leaf Spring For 6,000 Pound Axle on 5th Wheel Trailer
    Based on my research, your Dexter leaf spring is a double-eye leaf spring with a 3,000 pound capacity for your 6,000 pound axle. The original length of your existing springs is 25-1/4 inches. As springs tend to stretch a bit over time, your existing spring likely measures between 25-1/4 inches - 26 inches. To replace the springs on your axle, you can use the # e34SR leaf spring. This double-eye spring has a matching length, 25-1/4 inches, and weight capacity, 3,000 pounds, to your existing...
    view full answer...


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