{"product_id":"timbren-gmrck25dm1-2011-2023-gmc-chevy-2500-3500-rear-bump-stop-1in-spacer","title":"Timbren 2011-2023 GMC\/Chevy 2500\/3500 Custom Specs for GMRCK25D","description":"\u003ch4\u003eEliminate Rear Sag and Protect Your 2011-2023 Silverado or Sierra HD Under Heavy Loads with the Timbren GMRCK25DM1\u003c\/h4\u003e\n\u003cp\u003eThe Timbren GMRCK25DM1 is a rear suspension enhancement system (SES) bump stop upgrade for the 2011-2023 Chevrolet Silverado 2500HD, Silverado 3500HD, GMC Sierra 2500HD, and Sierra 3500HD in both 2WD and 4WD configurations.\u003c\/p\u003e\n\u003cp\u003eIt replaces the factory jounce stop on the frame with a purpose-engineered hollow rubber spring that engages progressively as load increases, preventing rear sag and controlling axle travel under heavy payloads and trailer tongue weight. Unlike traditional bump stops that only engage at the limits of suspension travel, the Timbren SES design contacts the axle in the normal travel range under load, providing a supplemental spring effect that works alongside the factory coil or leaf springs without requiring disassembly of the suspension. \u003c\/p\u003e\n\u003cp\u003eThe GMRCK25DM1 includes a 1-inch custom spacer for applications requiring additional preload or gap adjustment to achieve the correct half-inch to one-and-a-half-inch unloaded gap between the rubber spring and axle. Rated at 8,600 lbs capacity, it is engineered for trucks regularly used for towing, payload hauling, and commercial applications. Made in Canada.\u003c\/p\u003e\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eReplaces factory jounce stop with progressive hollow rubber spring for supplemental load support\u003c\/li\u003e\n\u003cli\u003ePrevents rear sag and controls axle travel under heavy payloads and trailer tongue weight\u003c\/li\u003e\n\u003cli\u003eProgressive spring rate increases resistance as load increases for automatic load leveling effect\u003c\/li\u003e\n\u003cli\u003eEngages within normal suspension travel range under load, not just at full compression\u003c\/li\u003e\n\u003cli\u003eIncludes 1-inch custom spacer for preload and gap adjustment\u003c\/li\u003e\n\u003cli\u003eRated at 8,600 lbs capacity\u003c\/li\u003e\n\u003cli\u003e2WD and 4WD compatible for 2011-2023 Chevy Silverado and GMC Sierra 2500HD and 3500HD\u003c\/li\u003e\n\u003cli\u003eNo disassembly of factory suspension required for installation\u003c\/li\u003e\n\u003cli\u003eMade in Canada by Timbren\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eVehicle Fitment\u003c\/h4\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eYear Range\u003c\/th\u003e\n\u003cth\u003eMake\u003c\/th\u003e\n\u003cth\u003eModel\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e2011-2023\u003c\/td\u003e\n\u003ctd\u003eChevrolet\u003c\/td\u003e\n\u003ctd\u003eSilverado 2500HD (2WD and 4WD)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2011-2023\u003c\/td\u003e\n\u003ctd\u003eChevrolet\u003c\/td\u003e\n\u003ctd\u003eSilverado 3500HD and 3500HD Cab and Chassis (2WD and 4WD)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2011-2023\u003c\/td\u003e\n\u003ctd\u003eGMC\u003c\/td\u003e\n\u003ctd\u003eSierra 2500HD (2WD and 4WD)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2011-2023\u003c\/td\u003e\n\u003ctd\u003eGMC\u003c\/td\u003e\n\u003ctd\u003eSierra 3500HD and 3500HD Cab and Chassis (2WD and 4WD)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch4\u003eSpecifications\u003c\/h4\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eDetail\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003ePart Number\u003c\/td\u003e\n\u003ctd\u003eGMRCK25DM1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBase Kit\u003c\/td\u003e\n\u003ctd\u003eGMRCK25D\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSpacer Thickness\u003c\/td\u003e\n\u003ctd\u003e1 inch\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSpring Material\u003c\/td\u003e\n\u003ctd\u003eHollow natural rubber (progressive rate)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRated Capacity\u003c\/td\u003e\n\u003ctd\u003e8,600 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUnloaded Gap Requirement\u003c\/td\u003e\n\u003ctd\u003e0.5 to 1.5 inches between spring and axle\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eShipping Weight\u003c\/td\u003e\n\u003ctd\u003e7 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCountry of Manufacture\u003c\/td\u003e\n\u003ctd\u003eCanada\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUPC\u003c\/td\u003e\n\u003ctd\u003eN\/A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch4\u003eWhat's Included\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e2x Timbren hollow rubber progressive rate spring bump stops (left and right)\u003c\/li\u003e\n\u003cli\u003e1-inch custom spacers\u003c\/li\u003e\n\u003cli\u003eHardware for installation\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eAbout Timbren\u003c\/h4\u003e\n\u003cp\u003eTimbren Industries is a Canadian manufacturer of suspension enhancement systems trusted by truck and van operators across North America for payload and towing load control. The Timbren SES product line is engineered for direct bolt-on fitment on a wide range of light truck, van, and SUV platforms, replacing factory bump stops with progressive hollow rubber springs that provide an automatic load-leveling effect without the air compressors, sensors, or maintenance requirements of air suspension systems.\u003c\/p\u003e\n\u003ch4\u003eRelated Parts on Our Site\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/products\/timbren-2011-2023-gmc-chevy-2500-3500-custom-specs-for-gmrck25d-1\"\u003eTimbren GMRCK25DM1.5 2011-2023 Chevy GMC 2500 3500 Rear Bump Stop 1.5-Inch Spacer - Same kit with a 1.5-inch spacer for additional preload adjustment\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eFrequently Asked Questions\u003c\/h4\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the Timbren GMRCK25DM1?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe Timbren GMRCK25DM1 is a rear suspension enhancement system (SES) upgrade for the 2011-2023 Chevrolet Silverado and GMC Sierra 2500HD and 3500HD. It replaces the factory rear jounce stops with progressive hollow rubber springs rated at 8,600 lbs to eliminate rear sag and control axle travel under heavy loads. The M1 suffix indicates the kit includes a 1-inch custom spacer for gap adjustment.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the difference between GMRCK25DM1 and GMRCK25DM1.5?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe GMRCK25DM1 includes a 1-inch spacer and the GMRCK25DM1.5 includes a 1.5-inch spacer. The spacer thickness adjusts the height and preload of the rubber spring relative to the axle. If your truck's unloaded gap between the bump stop and axle is greater than 1.5 inches, the larger spacer helps achieve the required half-inch to one-and-a-half-inch gap for correct operation. Timbren recommends measuring your specific gap before selecting the spacer size.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes the Timbren GMRCK25DM1 increase my truck's GVWR?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNo. Adding the Timbren SES does not increase the Gross Vehicle Weight Rating of your 2500HD or 3500HD. The GVWR is set by the vehicle manufacturer and is unchanged by this upgrade. The Timbren system improves load control and reduces sag, but the vehicle must not be loaded beyond its rated GVWR regardless of the suspension upgrade installed.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill the Timbren SES affect my ride quality when the truck is empty?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe Timbren SES is designed with a half-inch to one-and-a-half-inch gap between the rubber spring and the axle when the truck is unloaded. This gap means the rubber spring is not in contact with the axle during light driving, so the ride quality on an empty truck is not significantly affected. Once a load is applied and the suspension compresses enough to close the gap, the Timbren spring engages progressively to resist further sag.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eIs the Timbren GMRCK25DM1 compatible with factory lift or leveling kits?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe GMRCK25DM1 is engineered for stock ride height 2011-2023 Silverado and Sierra 2500HD and 3500HD trucks. Timbren recommends confirming the unloaded gap between the rubber spring and the axle falls within the half-inch to one-and-a-half-inch specification after any lift or leveling kit installation before ordering. The M1 or M1.5 spacer selection may need to change depending on how the lift affects that gap.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes the GMRCK25DM1 require any modification to the truck?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNo. The Timbren GMRCK25DM1 is a direct bolt-on replacement for the factory jounce stops. It requires no cutting, welding, or modification to the frame, axle, or suspension components. Standard hand tools are sufficient for installation.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow does the Timbren SES compare to helper springs or air bags?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe Timbren SES offers a maintenance-free alternative to helper leaf springs and air bag systems. Unlike air bags, the Timbren rubber spring requires no air compressor, no sensors, no lines, and no regular maintenance. Unlike helper springs, the progressive rubber design allows normal ride quality when unloaded. The trade-off is that Timbren does not allow adjustable load leveling the way an air bag system does, but for most hauling and towing applications the Timbren provides a simpler and equally effective solution.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes the GMRCK25DM1 fit the cab and chassis 3500HD variants?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eYes. The Timbren GMRCK25DM1 is compatible with the 2011-2023 Chevrolet Silverado 3500HD Cab and Chassis and the GMC Sierra 3500HD Cab and Chassis in addition to standard pickup configurations, in both 2WD and 4WD drivetrain configurations.\u003c\/p\u003e\n\u003ch4\u003eInstallation Instructions\u003c\/h4\u003e\n\u003col\u003e\n\u003cli\u003eSafely lift the rear of the vehicle and support it on jack stands. Verify the rear axle is supported and the vehicle is stable before beginning.\u003c\/li\u003e\n\u003cli\u003eLocate the factory jounce stop on the frame rail above the rear axle on each side.\u003c\/li\u003e\n\u003cli\u003eRemove the factory jounce stop by unbolting it from the frame bracket. Note the orientation and hardware for reference.\u003c\/li\u003e\n\u003cli\u003eMeasure the gap between the mounting surface and the top of the rear axle with the suspension at ride height to confirm spacer selection. The installed Timbren spring should produce a half-inch to one-and-a-half-inch gap between the bottom of the rubber spring and the axle pad with the truck empty.\u003c\/li\u003e\n\u003cli\u003eInstall the 1-inch spacer onto the Timbren mount bracket as needed to achieve the correct gap.\u003c\/li\u003e\n\u003cli\u003ePosition the Timbren GMRCK25DM1 onto the frame bracket and install using the provided hardware.\u003c\/li\u003e\n\u003cli\u003eTorque to the specification provided in the Timbren installation instructions included with the kit.\u003c\/li\u003e\n\u003cli\u003eRepeat for the opposite side.\u003c\/li\u003e\n\u003cli\u003eLower the vehicle and verify the unloaded gap between the rubber spring and axle pad is within the half-inch to one-and-a-half-inch specification on both sides.\u003c\/li\u003e\n\u003cli\u003eLoad the vehicle to a typical working load and verify rear sag is controlled and the truck sits level.\u003c\/li\u003e\n\u003c\/ol\u003e","brand":"Timbren","offers":[{"title":"Default Title","offer_id":46055291453519,"sku":"TIMGMRCK25DM1","price":269.36,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1062\/7920\/files\/timbren-gmrck25dm1-rear-bump-stops.jpg?v=1784119688","url":"https:\/\/www.blackopsautoworks.com\/products\/timbren-gmrck25dm1-2011-2023-gmc-chevy-2500-3500-rear-bump-stop-1in-spacer","provider":"Black Ops Auto Works","version":"1.0","type":"link"}