Description
The FOX® 987-24-055 2.5 Performance Series Rear IFP HTO Shock is a bolt-on rear shock for 2005-2016 Ford F-250 and F-350 Super Duty 4WD trucks running a 2-3.5 inch rear lift, delivering 11.19 inches of travel through a 2.5-inch smooth body design.
IMPORTANT: This shock is valved specifically for a 2-3.5 inch rear lift on 2005-2016 F-250 and F-350 Super Duty trucks. It is sold individually. This part number is one of a family of rear-specific 2.5 Performance Series shocks for this truck generation — FOX® 987-24-054 covers a 0-1.5 inch rear lift and FOX® 987-24-056 covers a 4-6 inch rear lift. Confirm your rear lift height before ordering, as installing the wrong variant will result in incorrect ride height and damping performance. Note this shock is built for the 2005-2016 Super Duty body style only and does not fit 2017-and-newer Super Duty trucks.
FOX® 2.5 Performance Series HTO shocks are bolt-on units built with position-sensitive technology, vehicle-specific valving, and larger pistons to improve on- and off-road performance over stock shocks. The 2.5-inch shock body is impact-extruded from 6061-T6 aluminum and features Type II clear-anodized plating that efficiently dissipates heat and resists corrosion.
An internal floating piston (IFP) separates the shock oil from the high-pressure nitrogen charge inside the shock body, keeping damping performance consistent and preventing oil aeration under hard use. High-flow, velocity-sensitive damping is tuned specifically for this application.
Hydraulic Top Out (HTO) technology adds usable, position-sensitive rebound damping control both on and off the pavement. HTO reduces harsh top-outs and increases ride comfort by forcing shock oil through a secondary shim stack to slow shaft speed near full extension — particularly beneficial after installing heavier, aggressive tires or when lifted higher than OEM specification.
The shock uses a 5/8-inch hard chrome-plated shaft with eyelet mounts on both ends. FOX® backs this shock with a Limited Lifetime Warranty.
- Fits 2005-2016 Ford F-250 and F-350 Super Duty 4WD trucks running a 2-3.5 inch rear lift
- 2.5″ impact-extruded 6061-T6 aluminum shock body with Type II clear-anodized plating
- Internal Floating Piston (IFP) separates shock oil from nitrogen charge
- Hydraulic Top Out (HTO) piston for position-sensitive rebound control
- High-flow, velocity-sensitive, application-specific damping
- 5/8″ hard chrome-plated shaft
- No reservoir, no external compression adjuster — direct bolt-on installation
- FOX® Limited Lifetime Warranty
- Sold individually
| Part Number | 987-24-055 |
| Position | Rear |
| Series | Performance |
| Body Diameter | 2.5″ |
| Travel | 11.19″ |
| Extended Length | 30.58″ |
| Compressed Length | 19.39″ |
| Top Mount | Eyelet |
| Bottom Mount | Eyelet |
| Shaft | 5/8″ hard chrome-plated |
| Piston Technology | Internal Floating Piston (IFP), Hydraulic Top Out (HTO) |
| Body Material | Impact-extruded 6061-T6 aluminum, Type II clear-anodized |
| Warranty | Limited Lifetime |
| Quantity | Sold individually |
This shock is designed for 2005-2016 Ford F-250 and F-350 Super Duty 4WD trucks (all trims) running a 2-3.5 inch rear lift as detailed above. This is a rear, lift-height-specific application for the pre-2017 Super Duty body style — confirm your exact rear lift height before ordering, and do not substitute this part number for 987-24-054 (0-1.5 inch rear lift) or 987-24-056 (4-6 inch rear lift), and do not use on 2017-and-newer Super Duty trucks.