Cognito Leaf Spring Mini Pack Kit | 2003-2013 Ram 2500 & 2003-2024 Ram 3500

The Obsidian Vision

The factory bottom overload spring on the 2003–2024 Ram 3500 and 2003–2013 Ram 2500 is a thick, two-stage leaf designed to prevent bottoming under maximum payload — a spring rate that is appropriate at the limit of the truck's load capacity but punishing in everyday unladen and lightly loaded driving where the overload engages prematurely and transmits road harshness directly into the cab. The Cognito Leaf Spring Mini Pack Kit replaces that harsh factory overload with a progressive-rate mini pack that converts the OEM two-stage leaf pack to a progressive pack, rides better across the full load range, and adds 1/2 to 1-1/4 inches of adjustable rear lift in 3/8-inch increments by removing the included spacer blocks. New center pins are included for fastening the mini pack to the stock spring pack. Longer U-bolts may be required and are not included — verify your U-bolt length before installation.

Concierge Fitment Guarantee

Every order is manually reviewed by our technicians to ensure 100% compatibility with your build before we ship.

Engineering Breakdown

• Converts the OEM two-stage rear leaf pack on the 2003–2024 Ram 3500 and 2003–2013 Ram 2500 to a progressive-rate pack by replacing the harsh factory bottom overload leaf with a multi-leaf progressive mini pack that engages gradually as load increases — eliminating the abrupt spring rate transition that causes the harsh ride quality associated with the factory two-stage overload design under light and moderate loads.
• Provides 1/2 to 1-1/4 inches of adjustable rear lift in 3/8-inch increments via removable spacer blocks, allowing the owner to select the desired lift height within the operating range without replacing the entire rear spring assembly — a cost-effective rear height adjustment for leveling applications, stance correction, or accommodating larger tires.
• Installs directly onto the stock spring pack using new center pins included in the kit, requiring no modification to the factory leaf spring assembly and maintaining full compatibility with the OEM rear suspension geometry at the adjusted ride height.

Progressive spring rate leaf packs achieve their compliance advantage by using thinner, more numerous leaves at the bottom of the pack that engage sequentially as load increases — providing a softer initial rate for light loads that firms progressively as the pack deflects under heavier loads. This is the same engineering principle used in full replacement leaf packs, applied to the overload position where the factory's single thick two-stage leaf creates the harshest ride quality impact. The spacer block system provides the rear lift adjustment in 3/8-inch increments: remove blocks to increase lift height within the 1/2 to 1-1/4 inch operating range. New center pins are included — do not reuse the factory overload center pin. Longer U-bolts may be required depending on the installed spacer block configuration and are not included in this kit — measure your existing U-bolt thread engagement after installation to determine if longer U-bolts are needed before torquing.

Audit Table

Verified Fitment (OFAS Standard)

✅ CONFIRMED — Ram 3500 (2012–2024):
2012–2024 Ram 3500 Big Horn, Laramie, SLT 2WD/4WD SRW & DRW
2013–2024 Ram 3500 Tradesman 2WD/4WD SRW & DRW
2016–2024 Ram 3500 Limited 2WD/4WD
2022–2024 Ram 3500 Limited Longhorn 2WD/4WD
2012–2022 Ram 3500 Lone Star 2WD/4WD
2012–2020 Ram 3500 Laramie Longhorn 2WD/4WD
2014–2020 Ram 3500 Laramie Limited 2WD/4WD
2012–2018 Ram 3500 ST 2WD/4WD
2013 Ram 3500 SXT

✅ CONFIRMED — Ram 2500 (2012–2013):
2012–2013 Ram 2500 Big Horn, Laramie, Laramie Longhorn, Lone Star, Outdoorsman, Power Wagon, SLT 2WD/4WD
2012 Ram 2500 ST
2013 Ram 2500 Tradesman

✅ CONFIRMED — Dodge Ram 3500 (2003–2011):
2003–2011 Dodge Ram 3500 ST, SLT, Laramie 2WD/4WD SRW & DRW
2011 Dodge Ram 3500 Laramie Longhorn
2010 Dodge Ram 3500 Power Wagon

✅ CONFIRMED — Dodge Ram 2500 (2003–2011):
2003–2011 Dodge Ram 2500 ST, SLT 2WD/4WD
2004–2011 Dodge Ram 2500 Laramie 2WD/4WD
2006–2011 Dodge Ram 2500 Power Wagon 4WD
2011 Dodge Ram 2500 Big Horn, Laramie Longhorn

❌ REQUIREMENTS:
Compatible with stock spring packs only — this mini pack is designed to fasten to the factory leaf spring assembly using the included center pins. Not compatible with aftermarket full replacement leaf packs.
⚠️ LONGER U-BOLTS MAY BE REQUIRED: Depending on the number of spacer blocks installed, the factory U-bolts may not provide adequate thread engagement after installation. Measure thread engagement after installation and before torquing — if engagement is insufficient, longer U-bolts must be sourced separately before driving. Longer U-bolts are not included in this kit.
Requires rear pinion angle check post-installation — verify driveline u-joint operating angles are within Dodge/Ram's specification for the installed lift height before towing at rated capacity.
Requires rear alignment verification post-installation to confirm axle centering and tracking geometry at the new ride height.

Installation & Technical Notes

Estimated Install Time: 1.5–2 Hours DIY Install (with basic lift equipment, hand tools, and torque wrench)
Lift Height Selection: Determine desired rear lift height before installation and remove the appropriate number of spacer blocks in 3/8-inch increments to achieve the target height within the 1/2 to 1-1/4 inch operating range. Verify final ride height after installation before driving.
Center Pin Installation: Use the new center pins included in the kit — do not reuse the factory overload center pin. Verify the center pin is fully seated and the nut is torqued to specification before reinstalling the U-bolts.
U-Bolt Check: After installation, verify that the factory U-bolts provide adequate thread engagement through the spring plate nuts. If thread engagement is less than the minimum required (typically 1.5x the bolt diameter), longer U-bolts must be sourced and installed before driving. Longer U-bolts are not included.
Torque Specifications: Refer to Cognito's included instruction sheet for center pin and U-bolt torque values — torque with the suspension at ride height under load.
Re-torque: Re-torque U-bolts and center pin hardware after the first 500 miles of use.

Wheel & Tire Fitment

The Cognito Leaf Spring Mini Pack Kit provides 1/2 to 1-1/4 inches of adjustable rear lift on the 2003–2024 Ram 3500 and 2003–2013 Ram 2500 platform. At this lift increment, no additional fender clearance modifications are required for standard tire sizes. For builds running 35-inch or larger tires, verify inner fender clearance at full compression with the new rear ride height before finalizing wheel and tire selection.

Our team is standing by to verify your specific spring pack configuration, desired lift height, and U-bolt requirements to confirm 215-91287 is the correct mini pack for your Ram build. Purchase with confidence; we review every build.