Cognito 1" SM Series Leveling Kit with Elka 2.5 Shocks | 2019-2025 AT4/AT4X/Trail Boss/ZR2

The Obsidian Vision

The AT4, AT4X, Trail Boss, and ZR2 arrive from the factory with elevated ride height and aggressive trim — but the front suspension geometry still carries a nose-down rake and shocks that leave measurable ride quality and damping performance unrealized, regardless of trim level. The Cognito 1-Inch SM Series Leveling Kit with Elka 2.5 Shocks resolves both conditions with a complete front-and-rear shock replacement and geometry correction package: the Cognito SM Series Ball Joint Upper Control Arm Kit corrects the ball joint angle, adds droop travel, and converts that gain into 1 inch of additional front ride height, while the Elka 2.5 Coilover Remote Reservoir front shocks and Elka 2.5 Piggyback Reservoir rear shocks deliver Dual Speed Compression-adjusted damping that is optimized for the T1 platform's weight, geometry, and the real-world demands of on-road, towing, and off-road use. Engineered, manufactured, and assembled in the USA, this is a complete, no-guesswork leveling system for the owner who demands elite ride quality and precise damping control from every component in the package.

Concierge Fitment Guarantee

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

Engineering Breakdown

• Corrects the front ball joint operating angle via the Cognito SM Series Upper Control Arm Kit, adding droop travel and converting that gain into 1 inch of additional front ride height — eliminating the factory nose-down rake while maintaining the minimum 3 inches of droop travel required for consistent ride quality and long-term suspension component integrity on the AT4/AT4X/Trail Boss/ZR2 platform.
• Eliminates the NVH, harshness, and damping limitations of the factory front and rear shocks through the Elka 2.5 Coilover Remote Reservoir front shocks and Elka 2.5 Piggyback Reservoir rear shocks, which use Dual Speed Compression adjustment to independently control low-speed damping (body roll, dive, squat) and high-speed damping (impact absorption, washboard, square-edge impacts) for a smoother, more predictable ride in all conditions.
• Maintains adequate droop travel at the 1-inch front lift increment to retain ride quality, tire contact patch, and long-term shock absorber integrity — the Cognito UCA's corrected geometry ensures the full droop travel range is available to the Elka shocks rather than being limited by ball joint bind at the elevated ride height.

The Cognito SM Series Ball Joint Upper Control Arms feature boxed sheet-metal construction, CNC robot-welded seams, and a semi-gloss black powder coat finish. Press-in ball joints are pre-installed and retained with black anodized, Cognito-branded laser-etched caps — a maintenance-free design that eliminates the grease interval associated with OEM-style ball joints. New crush sleeves and polyurethane bushings are included. The Elka 2.5 Coilover Remote Reservoir front shocks provide increased oil volume and thermal management relative to the factory front shocks, with the remote reservoir maintaining a constant oil supply to the piston to prevent cavitation and fade during sustained off-road or high-speed use. The Elka 2.5 Piggyback Reservoir rear shocks deliver the same reservoir-based thermal management to the rear suspension, replacing the factory rear shocks with a damping system that reduces rear-end bucking and lifting under hard acceleration and towing loads. Dual Speed Compression adjusters on all four shocks allow the owner to tune low-speed and high-speed compression independently, optimizing the damping character for their specific load, tire, and terrain requirements. All Cognito components are engineered, manufactured, and assembled in the USA. At 210 lbs, this kit ships via LTL freight carrier with residential delivery included.

Audit Table

Verified Fitment (OFAS Standard)

✅ CONFIRMED — AT4/AT4X/Trail Boss/ZR2 Models Only:
2019–2025 GMC Sierra 1500 AT4 4WD
2022–2025 GMC Sierra 1500 AT4X 4WD
2019–2025 Chevrolet Silverado 1500 LT Trail Boss 4WD
2019–2025 Chevrolet Silverado 1500 Custom Trail Boss 4WD
2022–2025 Chevrolet Silverado 1500 ZR2 4WD

❌ REQUIREMENTS:
⚠️ AT4/AT4X/Trail Boss/ZR2 Platform Specific: This kit is engineered for models that are factory 2 inches taller front and rear than standard Silverado/Sierra 1500 trims. This kit will bring the front up 1 additional inch and add droop travel for a level stance. Standard models (WT, Custom, LT, RST, LTZ, High Country, Denali) are not the intended application for this kit without additional rear lift components.
Requires front alignment immediately post-installation to reset caster and camber to specification.
Requires ADAS recalibration (adaptive cruise, forward collision alert, lane keep assist, Super Cruise) after installation.
Requires 4WD drivetrain.
Shipping Notice: At 210 lbs, this kit ships via LTL freight carrier. Residential delivery is included.

Installation & Technical Notes

Estimated Install Time: 5-Hour DIY Install (complete front and rear system, with basic lift equipment and hand tools)
Alignment Required: Yes — front caster and camber must be reset post-installation. Preferred caster: +3.5° to +4.5°; camber within ±0.5° of zero.
Torque Specifications: Refer to Cognito's included instruction sheet for all UCA and shock mount hardware torque values — torque all fasteners with the suspension at ride height.
DSC Adjuster Setup: Set all four Elka Dual Speed Compression adjusters to the softest position initially and tune incrementally based on load, tire size, and terrain preference. Front and rear adjusters can be tuned independently.
ADAS Recalibration: AT4X and ZR2 models with Super Cruise, adaptive cruise, forward collision alert, or lane-keep assist require front camera and radar recalibration after installation.
Shipping Notice: At 210 lbs, this kit ships via LTL freight carrier. Residential delivery is included. A delivery appointment will be scheduled by the carrier.

Wheel & Tire Fitment

Maximum Tire Size: 34x12" on a 9-inch wide wheel with 5.75-inch backspacing — confirmed clearance with this kit at the 1-inch front lift increment on AT4/AT4X/Trail Boss/ZR2 factory-elevated ride height
Wheel Width: 9 inches recommended for maximum tire size
Maximum Backspacing: 5.75 inches with 34x12" tires
Recommended Offset: 0mm to +18mm — negative offset wheels increase scrub radius and are not recommended with corrected-geometry upper arms

Our team is standing by to verify your specific trim (AT4, AT4X, Trail Boss, ZR2), ADAS configuration, and tire and wheel setup. Purchase with confidence; we review every build.