{"product_id":"bst-bssp-12-5-extended-square-u-bolts-kit-for-2-5-leaf-springs-9-16-bolts-complete-hardware-heavy-duty","title":"BST BSSP 12.5\" Extended Square U-Bolts Kit for 2.5\" Leaf Springs, 9\/16\" Bolts — Complete Hardware, Heavy-Duty","description":"\u003cp\u003e\u003cstrong\u003eBST BSSP 12.5\" extended square U-bolts kit secures 2.5\" wide leaf springs with 9\/16\" bolts on 1988–2019 Chevy Silverado\/GMC Sierra 1500 trucks.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eThis heavy-duty hardware set replaces or upgrades the U-bolts that clamp extended leaf springs to the axle on many full-size Chevy and GMC half-ton trucks. The kit includes four 12.5\" long square U-bolts sized for 2.5\" spring packs using 9\/16\" bolts, plus matching mounting hardware. It’s intended for applications where you’ve added or swapped rear blocks, fabricated extra leaf springs, or need longer U-bolts to accommodate lifted or modified rear suspension assemblies.\u003c\/p\u003e\n\n\u003ch3\u003eHow do these U-bolts fit my 1988–2019 Chevy Silverado or GMC Sierra 1500?\u003c\/h3\u003e\n\n\u003cp\u003eThe BST BSSP U-bolts are engineered for leaf springs that are 2.5\" wide and require a 12.5\" inside-bend length with 9\/16\" bolts. They are suitable for many stock and modified rear spring setups across model years listed. Verify spring pack width and required bolt diameter before ordering to ensure correct fitment.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eDesigned for 2.5\" wide leaf springs and 9\/16\" bolt holes\u003c\/li\u003e\n  \u003cli\u003e12.5\" measured from inside of the bend to match common extended spring needs\u003c\/li\u003e\n  \u003cli\u003eCompatible with 1988–2019 Silverado 1500, Sierra 1500, and C1500 rear suspensions\u003c\/li\u003e\n  \u003cli\u003eIncludes hardware for straightforward replacement of worn or undersized U-bolts\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat does the kit include and how is the hardware packaged?\u003c\/h3\u003e\n\n\u003cp\u003eThe package contains a set of four square U-bolts plus the necessary mounting hardware for installation. The parts are grouped so you get both driver- and passenger-side U-bolts and matching nuts and plates. This makes it easy to replace all rear U-bolts at once, ensuring even clamping and reliable alignment of the axle to the springs.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eFour 12.5\" long square U-bolts sized for 2.5\" springs\u003c\/li\u003e\n  \u003cli\u003eIncluded mounting plates and nuts for each bolt\u003c\/li\u003e\n  \u003cli\u003ePackaged as a complete set for left and right sides, front and rear placement\u003c\/li\u003e\n  \u003cli\u003eReady for direct swap or use with lifted\/repaired spring assemblies\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhy choose square U-bolts for leaf spring applications?\u003c\/h3\u003e\n\n\u003cp\u003eSquare U-bolts distribute clamping force over the spring perch and axle tube more evenly than round variants in many setups, reducing localized stress and helping keep spring packs aligned. For trucks with extended or added leafs, square U-bolts offer a reliable clamping footprint that resists shifting under load or during off-road driving.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eBetter contact on flat spring perches for improved clamp stability\u003c\/li\u003e\n  \u003cli\u003eReduced spring pack rotation and movement under load\u003c\/li\u003e\n  \u003cli\u003eDurable construction suited for towing, hauling, and lifted applications\u003c\/li\u003e\n  \u003cli\u003eIdeal when rear blocks or extra leaf springs increase stack height\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow should I inspect and install these U-bolts safely?\u003c\/h3\u003e\n\n\u003cp\u003eAlways replace U-bolts in matching sets and torque hardware to factory or axle-maker specifications. Inspect spring packs, perches, and axle tube for wear or deformation before installing new U-bolts. Use a calibrated torque wrench and recheck torque after the truck has been driven and re-settled under load.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eReplace all rear U-bolts at once for balanced clamping\u003c\/li\u003e\n  \u003cli\u003eTorque nuts to manufacturer specifications and retorque after initial use\u003c\/li\u003e\n  \u003cli\u003eCheck spring perches and axle tube for cracks, wear, or corrosion first\u003c\/li\u003e\n  \u003cli\u003eUse thread lubricant or anti-seize if recommended for your application\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for: This BST BSSP U-bolt kit is suited to DIY truck owners, mechanics, and fabricators working on 1988–2019 Chevy Silverado and GMC Sierra 1500 series vehicles who need longer U-bolts for extended or modified leaf spring setups. It’s useful when reassembling suspension after installing rear blocks, adding extra leafs, performing lift conversions, or replacing worn hardware to restore secure axle-to-spring clamping.\u003c\/p\u003e\n\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Will these U-bolts fit my 1999 Chevy Silverado 1500?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: If your rear leaf springs are 2.5\" wide and use 9\/16\" bolts, yes — they fit 1988–2019 Silverado 1500 models.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Are nuts and plates included with the U-bolt set?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes. The kit ships as a set of four 12.5\" U-bolts with the matching nuts and mounting plates.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"BST BSSP","offers":[{"title":"Default Title","offer_id":48086697836702,"sku":"B0CN6R1926","price":54.72,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0781\/2041\/9486\/files\/bst-bssp-front-packaging-ubolts.jpg?v=1785902113","url":"https:\/\/northtrailauto.ca\/products\/bst-bssp-12-5-extended-square-u-bolts-kit-for-2-5-leaf-springs-9-16-bolts-complete-hardware-heavy-duty","provider":"North Trail Auto","version":"1.0","type":"link"}