{"product_id":"umi-78-96-gm-b-body-rear-coil-over-conversion-brackets","title":"UMI Performance 3623 Rear Coilover Brackets for 1978-1996 GM B-Body Caprice RWD","description":"\u003ch4\u003eVehicle Fitment\u003c\/h4\u003e\u003cul\u003e \u003cli\u003e1978-1996 Chevrolet Caprice (All Trims, RWD)\u003c\/li\u003e \u003cli\u003e1994-1996 Chevrolet Impala SS (RWD)\u003c\/li\u003e \u003cli\u003e1991-1996 Buick Roadmaster (All Trims, RWD)\u003c\/li\u003e \u003cli\u003e1978-1985 Buick LeSabre (All Trims, RWD)\u003c\/li\u003e \u003cli\u003e1977-1981 Pontiac Bonneville (All Trims, RWD)\u003c\/li\u003e \u003cli\u003e1977-1981 Pontiac Catalina (All Trims, RWD)\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eFitment Notes\u003c\/h4\u003e\u003cul\u003e \u003cli\u003eBrackets-only kit - coilover shocks and springs are not included; purchase separately or upgrade to the complete kit (PN 3623-1 for sedans with 200 lb\/in springs, or PN 3623-2 for wagons with 250 lb\/in springs)\u003c\/li\u003e \u003cli\u003eUpper mount requires drilling with a standard 3\/8\" drill bit - no welding required for the brackets themselves\u003c\/li\u003e \u003cli\u003eFor sedan applications, UMI recommends a 200 lb\/in coilover spring rate; for wagon applications, 250 lb\/in is recommended\u003c\/li\u003e \u003cli\u003eFits factory GM B-Body rear axle housing - confirm axle is stock or stock-diameter replacement before ordering\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eFeatures\u003c\/h4\u003e\u003cul\u003e \u003cli\u003eConverts factory coil spring rear suspension to a fully functional rear coilover setup, enabling independent ride height and damping adjustability\u003c\/li\u003e \u003cli\u003eLaser-cut steel brackets JIG-welded at UMI for precise fitment on factory GM B-Body rear axles with consistent geometry across all units\u003c\/li\u003e \u003cli\u003eBolt-in double shear upper and lower mounting system - no welding required for bracket installation, preserving factory chassis integrity\u003c\/li\u003e \u003cli\u003eCompatible with Viking double-adjustable coilover shocks (used in UMI's complete 3623-1 and 3623-2 kits) and other industry-standard rear coilover shocks\u003c\/li\u003e \u003cli\u003e100% designed and manufactured in the USA\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eSpecifications\u003c\/h4\u003e\u003cul\u003e \u003cli\u003ePart Number: 3623\u003c\/li\u003e \u003cli\u003eProduct Name: Rear Coilover Conversion Brackets - 1978-1996 GM B-Body\u003c\/li\u003e \u003cli\u003eInstallation: Bolt-in double shear upper and lower mounts; upper mount requires 3\/8\" drilling\u003c\/li\u003e \u003cli\u003eBracket Construction: Laser-cut steel, JIG-welded\u003c\/li\u003e \u003cli\u003eRecommended Spring Rate - Sedan: 200 lb\/in\u003c\/li\u003e \u003cli\u003eRecommended Spring Rate - Wagon: 250 lb\/in\u003c\/li\u003e \u003cli\u003eCompatible Axle: Factory GM B-Body rear axle housing\u003c\/li\u003e \u003cli\u003eCountry of Origin: Made in the USA\u003c\/li\u003e \u003cli\u003eComplete Kit Options: PN 3623-1 (sedan, 200 lb\/in), PN 3623-2 (wagon, 250 lb\/in)\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eIncluded Components\u003c\/h4\u003e\u003cul\u003e \u003cli\u003e1x Set of UMI Rear Coilover Conversion Brackets (PN 3623)\u003c\/li\u003e \u003cli\u003e1x Hardware\/installation kit\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eProduct Description\u003c\/h4\u003e\u003cp\u003eThe UMI Performance 3623 is a bolt-in rear coilover conversion bracket kit engineered for the 1978-1996 GM B-Body platform, covering the Chevrolet Caprice, Impala SS, Buick Roadmaster, Buick LeSabre, Pontiac Bonneville, and Pontiac Catalina. The brackets replace the factory coil spring rear suspension setup with a coilover-compatible mounting system, enabling the use of adjustable coilover shocks for independent control of ride height and damping. Constructed from laser-cut steel and JIG-welded at UMI's Pennsylvania facility, the brackets are precision-fitted for factory GM B-Body rear axle housing dimensions without requiring cutting, fabrication, or welding to the chassis.\u003c\/p\u003e\u003cp\u003eInstallation uses a bolt-in double shear upper and lower mounting system; the only modification required is drilling the upper mount location with a standard 3\/8\" drill bit. This brackets-only kit is ideal for builders who already have coilover shocks on hand, or who want to select their own dampers. For a complete plug-and-play solution, UMI offers the 3623-1 (sedan, 200 lb\/in Viking double-adjustable shocks) and 3623-2 (wagon, 250 lb\/in) full coilover kits. Designed and manufactured 100% in the USA.\u003c\/p\u003e","brand":"UMI Performance","offers":[{"title":"Default Title","offer_id":53314468610367,"sku":"UMI3623","price":191.95,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0832\/7308\/9343\/files\/9b0bce3a98dee7a3bb14d569bf2854ebL.jpg?v=1780018021","url":"https:\/\/wcaperformance.com\/products\/umi-78-96-gm-b-body-rear-coil-over-conversion-brackets","provider":"WCA Performance","version":"1.0","type":"link"}