ICON V.S. 2.5 Aluminum Rear Piggyback Shocks for 2004-2026 Ford F-150

The ICON Vehicle Dynamics V.S. 2.5 Aluminum Series rear shock absorbers with piggyback reservoir and CDXS are application-specific performance shocks for 2009–2026 Ford F-150 and 2004–2008 Ford F-150 4WD, supporting 0–1 inch of rear lift over stock. Sold as a pair, each shock is built around a 2.5-inch hard-anodized aluminum body, a nitrogen-charged monotube design, and ICON's Compression Damping Dual Speed valving for independent high- and low-speed compression adjustment.

Shipping: ICON parts ship direct from ICON Vehicle Dynamics, mostly by UPS Ground. Lead times vary by part and some items are built to order, so please allow extra time. We email tracking as soon as your order ships.

Tuned for the Application, Not the Category

Unlike generic replacement shocks, the V.S. 2.5 Series is length- and valving-tuned for the specific F-150 application. That means the damping curve is calibrated for the truck's actual suspension geometry and weight, so the shock works as intended from the first mile rather than requiring extensive trial-and-error adjustment. Vehicle-specific valving also means the shock does not have to compromise between ride quality and off-road control the way a universal-fit unit does.

CDXS Dual-Speed Compression Adjustment

The CDXS system controls fluid flow under compression with two independent adjustment knobs: one for high-speed compression and one for low-speed compression, each with 10 detented settings. Low-speed adjustment governs body roll and handling response during cornering and braking; high-speed adjustment governs harshness over sharp impacts and rough terrain. Being able to set them independently means a driver can tune for a firm, controlled highway feel without sacrificing compliance over rocks or washboard.

Internal Bump Zone and Piggyback Reservoir

A 6061 billet aluminum manifold positioned below the top cap creates an internal Bump Zone that adds 20 percent of damping force as the shock approaches full compression. This progressive resistance helps prevent harsh bottom-outs during high-velocity compression without stiffening the shock throughout its normal travel range. The piggyback reservoir increases fluid volume, which improves heat dissipation and reduces shock fade during sustained off-road use where a standard shock body would overheat and lose consistency.

Features

• CDXS Dual-Speed Compression: 10 detented settings each for independent high- and low-speed compression adjustment
• Internal Bump Zone: 6061 billet aluminum manifold adds 20% damping force near full compression to resist bottom-outs
• Piggyback Reservoir: Nitrogen-charged monotube with external reservoir for improved heat dissipation and fade resistance
• 7/8" Shock Shaft: Induction-hardened, chrome-plated for durability and consistent seal performance
• 100% Rebuildable and Revalveable: Hard-anodized one-piece aluminum cylinder with PTFE-lined spherical bearings and application-specific mounting hardware
• 5WT Shock Oil: Premium-grade fluid for consistent damping across a wide temperature range

Specifications

Who This Is For and Isn't

These shocks suit 2009–2026 Ford F-150 owners and 2004–2008 Ford F-150 4WD owners running 0–1 inch of rear lift over stock who want independent dual-speed compression tuning, a rebuildable shock body, and improved fade resistance for sustained off-road use.

These shocks do not fit the F-150 Tremor, F-150 Raptor, or any F-150 equipped with the factory electronically controlled suspension system. They are also not compatible with models equipped with the BlueCruise system. They are not designed for rear lift exceeding 1 inch over stock.

Common Questions

What Ford F-150 years and configurations do these shocks fit?

These ICON V.S. 2.5 Aluminum rear shocks fit 2009–2026 Ford F-150 (all drive configurations except those noted below) and 2004–2008 Ford F-150 4WD models. They do not fit the F-150 Raptor, F-150 Tremor, or any F-150 with factory electronically controlled suspension or the BlueCruise system.

How much lift do these shocks support?

The ICON V.S. 2.5 Aluminum rear shocks are calibrated for 0–1 inch of rear lift over stock on most F-150 models. Lift heights are measured from a stock-equipped vehicle baseline; they are not designed for applications exceeding 1 inch of rear lift.

What does CDXS adjustment actually control?

CDXS (Compression Damping Dual Speed) provides two independent adjustment knobs on each shock: one for high-speed compression and one for low-speed compression, each with 10 detented positions. Low-speed controls body roll and handling response; high-speed controls harshness over sharp impacts. Adjusting them independently lets the driver tune street manners and off-road compliance separately.

Are these shocks rebuildable?

Yes. The ICON V.S. 2.5 Aluminum Series shocks are 100% rebuildable and 100% revalveable. The hard-anodized one-piece aluminum cylinder, PTFE-lined spherical bearings, and threaded body construction are all designed to be serviced rather than replaced as a unit.

Is a California Proposition 65 warning applicable?

Yes. These ICON shock absorbers contain chemicals known to the State of California to cause cancer, birth anomalies, or other reproductive harm. This warning applies to California residents under Proposition 65.