Fox 2.5 HTO Performance Series Rear Shock (SINGLE) 0"-1" 2001-2010 GM HD Truck (AX4075)

Fitment

The Axiom Supply AX4075 FOX 2.5 Performance Series Rear Shock is designed as a direct-fit performance upgrade for 2001-2010 GM HD trucks with stock-height through 1" lifted rear suspension configurations.

Chevrolet / GMC HD Trucks

Chevrolet Silverado 2500HD – 2001-2010

GMC Sierra 2500HD – 2001-2010

Chevrolet Silverado 3500 / 3500HD – 2001-2010

GMC Sierra 3500 / 3500HD – 2001-2010

Fitment Notes

Fits applicable 2WD and 4WD models.

Compatible with gas and Duramax diesel applications.

Designed for stock rear ride height through 1" of rear lift.

Compatible with factory rear suspension, up to approximately 1" rear block configurations, and airbag-assisted applications that maintain rear ride height within the shock's intended operating range.

Fits both 2001-2007 Classic and 2007.5-2010 New Body Style GM HD trucks.

Designed as a direct replacement using the factory-style rear shock mounting locations.

Sold Individually – Two shocks are required to service both rear positions.

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Features

FOX 2.5 Performance Series Technology – The large 2.5" shock body and piston assembly provide increased damping capacity and suspension control compared with smaller conventional replacement shocks.

Vehicle-Specific Performance Valving – Engineered around the weight, suspension architecture, and operating characteristics of the GM HD platform to provide controlled handling without sacrificing daily-driver comfort.

0–1" Rear Ride Height Range – Specifically sized for factory rear ride height through approximately 1" of rear lift, making the AX4075 an ideal rear shock for stock trucks, leveled trucks retaining near-stock rear height, and mild rear block configurations.

Internal Floating Piston Design – FOX's monotube IFP architecture separates the shock oil from the high-pressure nitrogen gas charge, helping prevent aeration and maintain consistent damping performance.

High-Flow Velocity-Sensitive Damping – Internal damping responds to shock shaft velocity, providing controlled suspension movement during larger impacts while remaining responsive to smaller road imperfections.

8.69" of Shock Travel – Provides substantial rear suspension travel to properly control axle movement through changing road surfaces, towing loads, and off-road terrain.

2.5" 6061-T6 Aluminum Body – Impact-extruded aluminum construction provides exceptional strength while efficiently transferring heat away from the shock oil.

Type II Clear-Anodized Finish – Protects the aluminum shock body against corrosion and harsh environmental exposure while maintaining FOX's distinctive premium finish.

5/8" Hard Chrome Shock Shaft – Heavy-duty shock shaft construction provides the strength and durability required for the weight and suspension loads generated by GM HD trucks.

Direct Bolt-On Installation – Utilizes factory-style eyelet upper and lower mounts for straightforward installation without custom brackets or modifications.

Built for Heavy-Duty Use – Engineered for daily driving, towing, hauling, larger tires, rough roads, job-site use, and off-road environments.

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Description

Race-Proven Performance. Heavy-Duty Truck Control. Daily Driver Comfort.

The Axiom Supply AX4075 FOX 2.5 Performance Series Rear Shock brings FOX's race-developed suspension technology to the rear of the 2001-2010 Chevrolet Silverado and GMC Sierra 2500HD and 3500HD platform in a simple direct bolt-on package.

The rear suspension of a heavy-duty truck has to perform under an extremely wide range of conditions. An unloaded truck may spend most of its time commuting on pavement, while the same suspension may later be asked to control thousands of pounds of payload or trailer tongue weight, larger tires, rough job-site roads, or demanding off-road terrain.

The AX4075 is designed to provide consistent suspension control throughout those changing conditions.

Rather than simply replacing the factory rear shock with another conventional damper, the AX4075 utilizes FOX's substantially larger 2.5" Performance Series monotube architecture to increase damping capacity and improve control over rear axle movement.

At the center of the shock is FOX's Internal Floating Piston system, which separates the shock oil from the high-pressure nitrogen gas chamber. Keeping the oil and gas isolated helps prevent aeration and allows the damping system to maintain more consistent performance as shock temperature and operating conditions change.

FOX combines this architecture with high-flow velocity-sensitive damping and vehicle-specific valving developed around the operating characteristics of the GM HD platform.

The result is a rear shock that remains comfortable and controlled during everyday driving while providing increased damping authority when the truck encounters broken pavement, repeated bumps, towing loads, washboard roads, larger suspension movements, or off-road terrain.

The AX4075 provides an impressive 8.69" of shock travel, allowing the shock to properly manage rear suspension movement while maintaining controlled compression and rebound characteristics throughout its operating range.

Its large 2.5" impact-extruded 6061-T6 aluminum body also provides excellent thermal management. Aluminum efficiently transfers heat away from the shock oil, helping maintain predictable damping performance during extended periods of demanding use.

A 5/8" hard chrome shock shaft, Type II clear-anodized body, premium internal components, and FOX's proven monotube construction complete a shock designed specifically for serious heavy-duty truck use.

The AX4075 is properly sized for stock rear ride height through approximately 1" of rear lift, making it an excellent match for leveled GM HD trucks that retain the factory rear suspension height, trucks utilizing a mild rear block, and airbag-assisted towing applications that remain within the intended shock operating range.

Pair the AX4075 rear shocks with the Axiom AX4074 FOX 2.5 Performance Series Front Shocks for a complete FOX 2.5 suspension package engineered around the 2001-2010 GM HD platform.

Whether your GM HD is a daily-driven Duramax, tow rig, work truck, leveled street truck, or off-road build, the Axiom Supply AX4075 FOX 2.5 Performance Series Rear Shock delivers the damping capacity, heat management, axle control, ride quality, and durability expected from a premium FOX suspension upgrade.

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Specifications

Axiom Part Number: AX4075

FOX Part Number: 987-24-075

Position: Rear

Series: FOX 2.5 Performance Series

Shock Type: Monotube IFP

Rear Ride Height: Stock / 0" through 1" Rear Lift

Shock Body Diameter: 2.5"

Body Material: Impact-Extruded 6061-T6 Aluminum

Body Finish: Type II Clear Anodized

Shock Shaft: 5/8" Hard Chrome

Damping: High-Flow Velocity-Sensitive

Travel: 8.69"

Extended Length: 25.88"

Compressed Length: 17.19"

Upper Mount: Eyelet

Lower Mount: Eyelet

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Includes

(1) Axiom Supply AX4075 FOX 2.5 Performance Series Rear Shock

FOX Part Number 987-24-075

Installation Bushings / Hardware as supplied with shock

SOLD INDIVIDUALLY

Quantity (2) required for complete rear shock replacement.

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Interchange

Axiom Supply AX4075

FOX 987-24-075

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The Axiom No-Nonsense Lifetime Warranty

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

Push it to the limit—we don't care.

If the part lets you down, we will make it up to you!