1. Trailer Leaf Spring Suspension
  2. Redline
  3. U-Bolts
  4. Axle Mounting Hardware
  5. Round Axle - 3 Inch
  6. 7-1/4 Inch Long
3" Round Trailer U-Bolts 9/16" Diameter (Qty 2)

3" Round Trailer U-Bolts 9/16" Diameter (Qty 2)

Item # SP01-080
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Our Price: $23.00
Trailer Leaf Spring Suspension
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Redline Axle Mounting Hardware - SP01-080
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3" Round Trailer U-Bolts Lowest Prices for the best trailer leaf spring suspension from Redline. 3" Round Trailer U-Bolts 9/16" Diameter (Qty 2) part number SP01-080 can be ordered online at etrailer.com or call 800-298-8924 for expert service.
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  • Reviews (16)
  • Q & A (2)
  • Videos (1)
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Redline Trailer Leaf Spring Suspension - SP01-080

  • U-Bolts
  • Axle Mounting Hardware
  • Round Axle - 3 Inch
  • 7-1/4 Inch Long
  • 5200 lbs - 7000 lbs
  • 9/16 Inch Diameter
  • Redline

3" Round Trailer U-Bolts


  • 3" Width
  • 9/16" Diameter
  • 7-1/4" Long
  • Includes Nuts

Used on 5.2K, 6K and 7K Axles

SP01-080 3" Round Trailer U-Bolts 9/16" Diameter (Qty 2)

Video of 3" Round Trailer U-Bolts 9/16" Diameter (Qty 2)

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

Video Transcript for Redline Trailer Suspension SP01-080 Review

Speaker 1: Today we're taking a look at a three inch round trailer U bolt kit. These U bolts act as a part of a trailer suspension system. They're typically used with U bolt plates to secure your axle to the leaf springs, which are mounted to your trailer's frame. U bolt plates are sold separately and available at etrailer.com if needed. This is a round U bolt design that fits round trailer axles. We're looking at durable steel construction, two U bolts and four nuts are included.

A few measurements to go over with real quick, starting with the inner width. Inside edge to inside edge is about 3 1/8 inches, so this designed for three inch diameter, round axles. The length measurement, from the bottom of the U to the end of the threads measures 7 1/4 inches. And then the bolt diameter is 9/16 of an inch. That's gonna do it for today's look at the three inch round trailer U bolts..

Customer Reviews

3" Round Trailer U-Bolts 9/16" Diameter (Qty 2) - SP01-080

Average Customer Rating:  5.0 out of 5 stars   (16 Customer Reviews)

3" Round Trailer U-Bolts

- SP01-080
by: 09/03/2020

Went on easy! 873664

- SP01-080

got my order today I believe it was ahead of time, everything looks good. I think they are exactly the parts I need for my rearend setup.. 767793

- SP01-080

Was exactly what I needed 766856

- SP01-080

good items, fit perfectly 728151

- SP01-080

Received all parts quickly and correctly. customer service is excellent. Thank You. 714434

- SP01-080

All the parts look good. Have not installed them yet. 641341

- SP01-080

Exactly what I needed and arrived quick ly. 616374

- SP01-080

Easy to order, super fast shipping, and great follow up. 560573

- SP01-080

Size was accurate and are well made. Th anks. 553786

- SP01-080

Very easy to view and purchase Nice tech sheets attached to catalog item on website. I would definitely use agIn Thanks Mike 330455

- SP01-080

Parts arrived superfast and great quality thanks for your unmatched service 171720

- SP01-080

Very happy with the product and received in just a couple of day's. 167345

Perfect, could not be happier
Doug F - 01/04/2016


- SP01-080

'U' bolts the correct size. I am please d. 144764

- SP01-080

Just what I was expecting. The web site is well set up. I like you has standard information about trailer parts. Keep in mind regular people like me only know about what I have, its nice to see as much information about what is standard and all different kinds of springs and axles. Also like you have free shipping on orders over a hundred dollars. 135561

- SP01-080

Fit Like a Glove! Fine thread & 9/16", heavy duty (1/2" are standard) 94371

- SP01-080

No problems here, excellent products, helpful staff, quick shipping, very satisfied thanks etrailer 69321


Ask the Experts about this Redline Trailer Leaf Spring Suspension

  • Corrosion Resistant Leaf Spring Mounting Hardware for 3 inch Round Axle with 2 Inch Leaf Springs
    We do indeed offer U-bolt and plate kits for a 3 inch diameter axle tube that can be used on 2 inch wide springs, part # APUBR-9 for a 7-1/4 inch long U-bolt or # APUBR-8 for a 7 inch U-Bolt. These bolts and plates are constructed of steel and aren't galvanized. We do offer galvanized U-bolts and zinc plated plates separately. For a 7 inch long by 1/2 inch diameter galvanized U-bolt suitable for a 3 inch round axle and 2 inch wide spring, use part # 1755892-Z. For a U-bolt plate for...
    view full answer...
  • Torque Ratings for Trailer U-Bolts on 3" Round Axle
    Trailer U-bolts will have different torque specs depending on their diameter. For your 2006 Montana 3650RK 5th wheel trailer, which will likely have 3" round axles (though you will want to verify), you will need either 3" Round Trailer U-Bolts 9/16" Diameter # SP01-080 or 1/2" Diameter # SP01-060. The correct torque specs are: - 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 I have added a link to a help article on...
    view full answer...

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Info for this part was:

Updated by:
Adele M
Installed by:
Cole B
Test Fit:
Clayton O

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