Torque Ratings for Trailer U-Bolts on 3" Round Axle
Updated 02/10/2025 | Published 06/29/2020 >
Products Featured in This Question
Question:
Torque specs for Ubolts on 2006 Montana 5th wheel model, 3650 Rk. Are torque specs the same for round ubolts as well as square ubolts? Thanks!
asked by: Stephen H
Helpful Expert Reply:
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 trailer suspension which this info as well as a lot of similar information
Product Page this Question was Asked From
3" Round Trailer U-Bolts (Qty 2)
- Trailer Suspension Parts
- U-Bolts
- Camper
- Car Hauler
- Utility Trailer
- 5200 lbs - 7000 lbs
- Round Axle - 3 Inch
- 1/2 Inch Diameter
- 7 Inch Long
- Dexter
more information >
Featured Help Information
Miscellaneous Media
Continue Researching
- Shop: Roadmaster Comfort Ride Leaf Spring Suspension Kit w/ Shocks - Tandem 8K, 3" Trailer Axles
- Shop: U-Bolt Kit for Mounting 5,200-lb to 7,000-lb, Round Trailer Axles - 7-1/16" Long U-Bolts
- Shop: 3" Round Trailer U-Bolts 9/16" Diameter (Qty 2)
- Shop: Roadmaster Comfort Ride Leaf Spring Suspension Kit w/ Shock Absorbers - Tandem 7K Trailer Axles
- Shop: Roadmaster Comfort Ride Leaf Spring Suspension Kit w/ Shocks - Tandem 5.2K-7K Axles
- Shop: CE Smith U-Bolt Kit for Mounting 3,500-lb, Round Trailer Axles - 5-1/2" Long U-Bolts - Zinc
- Shop: MORryde X-Factor Crossmember for Standard Frame Hangers
- Video: The Low-Down on the U-Bolt Kit for Mounting 5,200-lb to 7,000-lb, Round Trailer Axles
- Video: Review of Roadmaster Trailer Leaf Spring Suspension - Springs - RM-2460-2570
- Video: Installing the Roadmaster Comfort Ride Leaf Spring Suspension Kit on a 2023 Grand Design Solitude Fi
- Video: Roadmaster Comfort Ride Leaf Spring Suspension Kit Installation Guide - 2022 Grand Design Solitude F
- Search Results: disc brakes brake actuator
- Search Results: brake actuator
- Search Results: morryde x~factor crossmember
- Search Results: deemaxx trailer brakes
- Search Results: morryde xfactor
- Search Results: 7 leaf trailer leaf springs
- Q&A: Recommended 5th Wheel Trailer Suspension Upgrade for a 2022 Jayco Northpoint 310RLTS
- Q&A: Can Thicker U-Bolts Be Used for Trailer Axle
- Q&A: How to Determine Correct U-Bolt Kit and Leaf Spring Bushing for a 6,000 Lb Trailer Axle
- Q&A: U-Bolt Kit and Bracket for a 3" Trailer Axle
- Video: Roadmaster Comfort Ride Leaf Spring Kit Install - 2015 Keystone Raptor 5W Toy Hauler
- Video: MORryde Standard Frame Hanger X-Factor Crossmember Installation - 2022 Grand Design Imagine Travel T
- Video: Detailed Breakdown of the Replacement U-Bolt w/Nuts for 8,000-lb, Round Trailer Axles
- Search Results: morryde step above
- Q&A: Will the Removable Mounting Plate for MORryde StepAbove RV Steps Work With Strut Assist Models
- Q&A: How to Determine if Trailer Axle is Not Aligned and How to Measure to Replace Trailer Axle
- Q&A: Is it Best to Use Three MORryde X-Factor Crossmembers with Tandem Axle Trailer




Dave P.
2/10/2025
Kyle, why do the torque specs have a range, ie... 9/16 inch bolts 65ft-lbs - 95ft-lbs? That's a big difference. How do we narrow down exactly what ft-lbs to torque to?