{"product_id":"aupar-trailer-u-bolt-kit-for-3-round-axles-7-long-1-2-dia-includes-tie-plates-locking-hardware","title":"Aupar Trailer U-Bolt Kit for 3\" Round Axles — 7\" Long 1\/2\" Dia, Includes Tie Plates \u0026 Locking Hardware","description":"\u003cstrong\u003eHeavy-duty Aupar U-bolt kit secures 3\" round trailer axles and leaf springs with two 7\" long, 1\/2\" diameter U-bolts, tie plates and locking hardware.\u003c\/strong\u003e\n\n\u003cp\u003eThis Aupar kit contains the hardware needed to fasten a 3-inch round axle to 1-3\/4\" leaf spring assemblies on trailers rated roughly in the 5,200–7,000 lb range. Engineered for trailer use, the set includes two U-bolts, four tie plates sized for common leaf springs, lock nuts, and spring washers to resist loosening from vibration. Components are built from high-grade steel and finished for durability so you can replace worn mounting hardware or perform an axle rebuild with parts sized to fit popular axle brands.\u003c\/p\u003e\n\n\u003ch3\u003eWill these U-bolts fit my trailer axle and springs?\u003c\/h3\u003e\n\u003cp\u003eThey are made specifically for 3\" round axles and 1-3\/4\" leaf spring packs, with U-bolt legs 7\" long and 1\/2\" in diameter. Confirm your axle outside diameter and spring plate width before ordering to ensure a correct match.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eU-bolt internal diameter: for 3\" round axles\u003c\/li\u003e\n  \u003cli\u003eLeg length: 7\" to accommodate typical spring stacks and plates\u003c\/li\u003e\n  \u003cli\u003eThread size: 1\/2\" diameter nuts supplied\u003c\/li\u003e\n  \u003cli\u003eIncluded tie plates sized for 1-3\/4\" leaf springs\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow does the kit resist loosening under road vibration?\u003c\/h3\u003e\n\u003cp\u003eAupar includes upgraded spring washers and lock nuts to reduce the risk of fastener back-off from vibration and load cycling. The washers bite slightly and maintain clamping force while the improved plate shape spreads load more evenly across the clutch points.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eSpring washers that help hold torque under vibration\u003c\/li\u003e\n  \u003cli\u003eLock nuts supplied for additional thread security\u003c\/li\u003e\n  \u003cli\u003eRedesigned tie plates for uniform pressure distribution\u003c\/li\u003e\n  \u003cli\u003eSteel construction provides consistent clamp strength\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat construction and finish should I expect?\u003c\/h3\u003e\n\u003cp\u003eThe kit is manufactured from high-quality steel for strength and longevity, with a corrosion-resistant finish suitable for trailer environments. These materials deliver the stiffness and load-bearing capacity required for axle mounting while helping slow surface rust in typical road conditions.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eHigh-grade steel U-bolts and plates for strength\u003c\/li\u003e\n  \u003cli\u003eProtective finish to resist moisture and road debris\u003c\/li\u003e\n  \u003cli\u003ePrecision threads for reliable nut engagement\u003c\/li\u003e\n  \u003cli\u003eRobust plate design to reduce local deformation\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow easy is installation and what hardware is included?\u003c\/h3\u003e\n\u003cp\u003eInstallation is straightforward for anyone familiar with trailer axle work: lift and support the trailer, position plate and spring, fit U-bolts over axle and through plate, then torque the nuts to spec. The kit includes everything needed for a two-U-bolt axle clamp on one side of an axle.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eTwo 7\" U-bolts with 1\/2\" diameter legs\u003c\/li\u003e\n  \u003cli\u003eFour tie plates sized for 1-3\/4\" springs\u003c\/li\u003e\n  \u003cli\u003eLocking nuts and spring washers included\u003c\/li\u003e\n  \u003cli\u003eHardware quantity suited for one axle end (two U-bolts total)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for: The Aupar Heavy Duty Trailer U-bolt Kit is aimed at trailer owners, DIY mechanics, and small fleet maintainers replacing worn axle clamps or upgrading mounting hardware on 3\" round axles paired with 1-3\/4\" leaf springs. It's a practical match for common axle brands used in light-to-medium duty trailers when you need reliable, trailer-specific mounting hardware that balances strength, corrosion protection, and vibration resistance.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Do these U-bolts fit 3-inch round axles?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes — the kit is sized specifically for 3\" round axles with 7\" leg length and 1\/2\" diameter hardware.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Is lock hardware included to prevent loosening?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes — the kit includes spring washers and lock nuts to help resist vibration-induced loosening.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"Aupar","offers":[{"title":"Default Title","offer_id":48083887128734,"sku":"B0CNCXT379","price":67.98,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0781\/2041\/9486\/files\/aupar-front-packaging.jpg?v=1785838777","url":"https:\/\/northtrailauto.ca\/products\/aupar-trailer-u-bolt-kit-for-3-round-axles-7-long-1-2-dia-includes-tie-plates-locking-hardware","provider":"North Trail Auto","version":"1.0","type":"link"}