Choosing the right trailer U bolt kit is essential for dependable suspension and secure attachment of leaf springs. This guide highlights five well-reviewed options that cover common axle sizes, thread pitches, and pack quantities, helping you identify durable hardware with corrosion resistance and easy installation.
style=”display:none;”>Product Summary Table
| Product | Brand | Axle Type / Size | U Bolts (Length) | Diameter | Pack / Extras |
|---|---|---|---|---|---|
| SPARKWHIZ Trailer U Bolt Kit 7 inch | SPARKWHIZ | 3″ Round Axle, 5,200-7,000 lb | 8 x 7″ long | 1/2″ | 2 U-bolts, nuts, tie plates |
| MCCKLE Trailer U Bolt Kit 5-1/2″ | MCCKLE | 2-3/8″ Round Axle, 3,500 lb | 5-1/2″ | 1/2″ | 2-4 U-bolts, nuts, washers |
| JUFWKO Replace 1900-2-1600 U-Bolt Kit | JUFWKO | B&W Gooseneck Turnoverball Hitches | Custom size | Varies | High-strength, galvanized |
| SPARKWHIZ 5-1/2″ U Bolt Kit for 3,500 lb Axle | SPARKWHIZ | 2-3/8″ Round Axle, 3,500 lb | 5-1/2″ | 1/2″ | 2-4 U-bolts, nuts, washers |
| SPARKWHIZ 5-1/2″ U Bolt Kit 2 Pack | SPARKWHIZ | 2-3/8″ Round Axle, 3,500 lb | 5-1/2″ | 1/2″ | 2 U-bolts per kit, nuts, washers |
SPARKWHIZ Trailer U Bolt Kit 7 inch for 5,200-7,000 lb Trailer Axle
Designed for 3″ round axles in the 5,200–7,000 lb range, this kit includes eight 7-inch U-bolts with a 1/2″ diameter and 2″ thread pitch, plus 16 nuts and four tie plates for 1-3/4″ leaf springs. The kit uses durable steel and offers rust and corrosion resistance, supporting a robust trailer suspension. It is positioned as a ready-to-install upgrade for heavy-duty trailers and is paired with accessories that simplify mounting and reliability in demanding towing conditions.
MCCKLE Trailer U Bolt Kit 5-1/2″ For 3500 Lb Axle
Specifically sized for 2-3/8″ round axles up to 3,500 lbs, this MCCKLE kit includes five-and-a-half inch long U-bolts, 1/2″ diameter, and a complete set of nuts and washers. The kit emphasizes easy installation and rust resistance through corrosion-protective coating. It offers a practical option for routine trailer maintenance and safer towing performance by reinforcing critical suspension points.
JUFWKO Safety Chain U-Bolt Kit for B&W Gooseneck
This kit is designed to match B&W gooseneck turnoverball hitches and serves as a replacement U-bolt assembly when original hardware is damaged. It features galvanized, high-strength construction for corrosion resistance and durability under heavy towing and vibration. The reinforced U-shaped structure helps maintain a secure connection across rough roads and long hauls, making it a suitable option for replacing failing fixings on rugged trailers.
SPARKWHIZ 5-1/2 Inch U Bolt Kit for 3,500 Lb Axle
Targeted at a 2-3/8″ round axle carrying up to 3,500 lbs, this SPARKWHIZ U-bolt kit includes four 5-1/2″ long U-bolts with 1/2″ diameter threads, plus eight nuts and two tie plates for 1-3/4″ leaf springs. The components are built from durable steel with rust and corrosion resistance. The kit is pitched as a convenient upgrade for mid-range trailer suspensions, offering a balance of length and strength for reliable towing performance.
SPARKWHIZ Trailer U Bolt Kit 5-1/2″ 2 Pack for 3,500 Lb Axle
This 2-pack from SPARKWHIZ provides two 5-1/2″ U-bolts designed for a 2-3/8″ round axle rated around 3,500 lbs. Each kit includes 1/2″ diameter bolts, 16 nuts, and 4 tie plates suitable for 1-3/4″ leaf springs. The kit emphasizes rust resistance and durability for frequent towing, offering cost-effective redundancy for spare parts or fleet maintenance. It is suitable for trailer owners who prefer multiple U-bolt assemblies in one purchase.
Buying Guide: Key Purchase Considerations for Trailer U Bolt Kits
To select the best U-bolt kit for your trailer, consider axle size, weight rating, and leaf spring configuration. Verify the bolt length and thread pitch to ensure a proper fit with your springs and mounting plates. Corrosion resistance matters for exposure to road salt and wet environments, so galvanized or coated steel is preferable. Check included hardware—nut type, washers, and tie plates—so the kit covers installation needs without extra purchases. For fleets or multiple trailers, a 2-pack or kit with extra U-bolts can reduce downtime. Finally, confirm compatibility with your trailer model and hitch system to prevent improper tension or misalignment during towing. Compare durability, ease of installation, and price-per-pair to determine value over time.
Consider these perspectives when evaluating options:
– Replacement vs. upgrade: If you’re replacing worn U-bolts, focus on matching diameter and thread pitch exactly.
– Heavy-duty vs. standard use: Heavy-duty kits tend to use longer U-bolts and stronger nuts, which may be overkill for lighter trailers.
– Environmental exposure: For saltwater or winterized roads, galvanized or coated finishes extend life.
– Installation effort: Kits with included tie plates and nuts simplify maintenance by reducing parts on-hand requirements.
In summary, the right trailer U bolt kit balances axle compatibility, load rating, and corrosion resistance, while offering practical installation and long-term reliability for safe, consistent towing.