Axiom Supply Stage 3 FOX 2.5" Performance Elite Leveling System GM HD Truck 2500 / 3500 Silverado / Sierra 2011-2019

Fitment

The Axiom Supply Stage 3 FOX 2.5 Performance Elite Leveling System is our most advanced suspension package for GM HD trucks, combining premium ride height correction, suspension geometry optimization, and race-inspired FOX Performance Elite shock technology into one complete system.

Applications include:

2011-2019 Chevrolet Silverado 2500HD

2011-2019 GMC Sierra 2500HD

2011-2019 Chevrolet Silverado 3500HD

2011-2019 GMC Sierra 3500HD

Fitment Notes

Provides up to 2" of front ride height adjustment.

Designed for stock, leveled, and lifted applications.

Includes vehicle-specific FOX Performance Elite Series 2.5 Reservoir shocks properly sized and valved for leveled GM HD trucks.

Compatible with most aftermarket suspension systems utilizing factory-style upper control arm mounting locations.

Oversized tires exceeding 11.50" in width may contact the control arm when used with certain factory wheel configurations.

Additional wheel offset or wheel spacers may be required depending on tire size and wheel combination.

Features

FOX Performance Elite 2.5 Reservoir Shocks – Includes a complete set of FOX Performance Elite Series 2.5 Reservoir shocks engineered to deliver exceptional ride quality, increased damping control, and race-proven performance both on and off-road.

External Reservoir Technology – Remote reservoirs increase shock oil and nitrogen capacity, allowing for improved heat management, greater damping consistency, and enhanced performance during prolonged off-road use, towing, and heavy-duty operation.

Race-Proven FOX Performance – Derived directly from FOX off-road racing technology and validated in the harshest environments, Performance Elite shocks deliver the precise control and durability demanded by serious truck enthusiasts.

Large-Bore 2.5-Inch Shock Bodies – Increased piston area and fluid volume provide exceptional damping capacity, improved vehicle stability, and greater resistance to fade compared to factory shock absorbers.

Vehicle-Specific Shock Tuning – Each FOX Performance Elite shock is selected specifically for leveled GM HD applications to provide balanced ride quality, enhanced control, and predictable handling across a wide range of driving conditions.

Internal Floating Piston Design – Monotube IFP architecture separates shock oil from high-pressure nitrogen to maintain consistent damping performance under demanding conditions.

Type II Hard-Anodized Aluminum Bodies – Lightweight aluminum construction efficiently dissipates heat while providing outstanding corrosion resistance and long-term durability.

True Double-Shear Construction – Built from identical upper and lower 3/16" steel plates that are precision laser cut and hand welded into a single rigid structure. This true double-shear architecture distributes suspension loads evenly while maximizing strength, rigidity, and long-term durability.

Equipped with AX6292 Grade 12.9 Ball Joints – Every kit includes a pair of Axiom Supply AX6292 bolt-on upper ball joints featuring our Grade 12.9 Extreme-Duty Ball Stud technology for exceptional strength, steering precision, and resistance to deformation under heavy loads.

Forged Torsion Leveling Keys – Designed to provide additional front ride height while maintaining proper torsion bar indexing and adjustment range.

Corrected Suspension Geometry – Restores proper suspension operating angles while improving droop travel and overall suspension performance.

Dual-Position Ball Joint Mounting – Allows the ball joint to be mounted above or below the control arm mounting plate, providing additional flexibility when dialing in alignment settings and suspension geometry.

Precision Laser-Cut Components – Manufactured using computer-designed, laser-cut steel components for exceptional fitment consistency and manufacturing accuracy.

Service-Friendly Design – Improved grease fitting access simplifies routine maintenance and lubrication regardless of control arm orientation.

Premium Bushing System – High-quality bushings and sleeves provide smooth articulation while minimizing unwanted suspension deflection.

Built for Heavy-Duty Use – Engineered to withstand the demands of towing, oversized tires, lifted suspension systems, off-road use, and daily driving.

Lifetime Warranty Protection – Backed by the Axiom No-Nonsense Lifetime Warranty for the original purchaser.

Description

The Axiom Supply Stage 3 FOX 2.5 Performance Elite Leveling System represents the pinnacle of our GM HD suspension lineup. Developed for truck owners who demand maximum capability, premium ride quality, and uncompromising suspension performance, this system combines Axiom's most advanced suspension correction components with FOX's flagship Performance Elite shock technology.

At the foundation of the system are Axiom Supply forged torsion leveling keys, providing up to 2" of front ride height adjustment to eliminate factory rake and create clearance for larger tire and wheel combinations. Unlike conventional leveling kits, the Stage 3 Performance Elite System is engineered as a complete suspension package that addresses both ride height and suspension performance.

Included in every kit is a complete set of FOX Performance Elite Series 2.5 Reservoir shocks. Drawing directly from FOX's off-road racing heritage, these shocks are engineered to deliver exceptional damping control, ride quality, and durability in the harshest environments. Their large-bore 2.5-inch shock bodies provide increased fluid volume and piston area, while the external reservoir dramatically increases oil and nitrogen capacity for superior thermal management and fade resistance.

The Performance Elite reservoir design allows the shocks to maintain consistent damping characteristics even during prolonged off-road use, heavy towing, high-speed rough terrain driving, and other demanding operating conditions. The result is improved suspension composure, enhanced stability, and precise vehicle control when conditions are at their toughest.

FOX's monotube Internal Floating Piston (IFP) design separates shock oil from high-pressure nitrogen, ensuring consistent damping performance while reducing aeration under extreme use. Combined with application-specific valving selected specifically for leveled GM HD trucks, the Performance Elite package delivers a ride quality and level of control far beyond what factory shocks can provide.

To ensure suspension geometry remains optimized after leveling, the system includes Axiom Supply Heavy-Duty Upper Control Arms featuring a true double-shear construction utilizing identical upper and lower 3/16" steel plates hand welded into a rigid boxed structure. This design distributes suspension loads evenly through the ball joint mounting area while minimizing flex and maintaining alignment integrity under demanding conditions.

Each control arm is equipped with Axiom Supply AX6292 Bolt-On Upper Ball Joints featuring our Grade 12.9 Extreme-Duty Ball Stud technology. Combined with the arm's dual-position ball joint mounting system, installers gain additional alignment flexibility while benefiting from one of the strongest bolt-on upper ball joints available for the GM HD platform.

The result is a complete suspension package engineered to improve stance, ride quality, suspension control, wheel travel, and long-term durability without compromise.

Whether your truck is built for towing, overlanding, off-road exploration, worksite duty, or simply demands the very best suspension components available, the Axiom Supply Stage 3 FOX 2.5 Performance Elite Leveling System delivers race-inspired performance with everyday reliability.

Maintenance

Apply 3 pumps of grease to each ball joint during installation.

For continued performance, service each ball joint every 5,000–7,000 miles. Use only the amount of grease necessary to lubricate the joint and avoid over-greasing.

Includes

(2) Axiom Supply Heavy-Duty Upper Control Arms

(2) Axiom Supply AX6292 Grade 12.9 Bolt-On Upper Ball Joints

(2) Axiom Supply Forged Torsion Leveling Keys

(2) FOX Performance Elite Series 2.5 Reservoir Front Shocks

(2) FOX Performance Elite Series 2.5 Reservoir Rear Shocks

(4) Control Arm Sleeves

(8) Control Arm Bushings

Complete Installation Hardware Kit

Installation Instructions

The Axiom No-Nonsense Lifetime Warranty

Our suspension and steering components are warrantied for life to the original purchaser against manufacturer defects, premature wear, or breakage.

Push it to the limit—we don't care.

If the part lets you down, we'll make it right.