FOX Factory Series Rear Reservoir Shock 1999-2016 Ford Super Duty 0–5.5″ Lift
1999–2016 Ford F-250/F-350/F-450/F-550 Super Duty Rear Fox 2.5 Factory Race Series Reservoir Shock
Upgrade your suspension with race-proven performance from FOX. The Factory Race Series 2.5 Reservoir smooth body shocks deliver enhanced ride quality and the control you need when heading off the pavement. Built using technology derived from FOX’s off-road race shocks, these dampers have been tested and refined in extreme conditions to provide consistent, reliable performance for your truck or SUV.
The external reservoir increases oil and nitrogen capacity, improving heat dissipation and damping consistency while also delivering a true race-inspired look. Designed for both stock and lifted applications, these bolt-on shocks provide precise control and improved handling across any terrain. Experience the confidence and performance that comes from FOX’s competition-driven engineering.
Key Features
2.5” Smooth Body Shock Design
Large diameter body increases oil capacity for better cooling and consistent damping under heavy use.
External Reservoir
Improves thermal performance and reduces shock fade during aggressive driving or off-road use.
Race-Proven Performance
Derived directly from FOX off-road racing technology and tested in extreme conditions.
Application-Specific Valving
Tuned to maximize ride quality, control, and performance for your specific vehicle.
Bolt-On Installation
Designed for straightforward installation using factory mounting locations.
Specifications
- Series: Factory Race Series
- Travel: 11.37"
- Body: 2.5" smooth bore zinc-plated seamless steel body
- Body Plating: Zinc-plated and double clear coated for long-lasting finish
- Components: Black-anodized CNC-machined 6061-T6 billet aluminum
- Shaft: 7/8" hard chrome plated heat-treated alloy steel
- Piston: Race-developed high-flow piston design
- Valving: Application-specific valving to maximize performance
- Seals: Redundant sealing pack system (main seal, wiper seal, scraper seal)
- Bearings: PTFE-lined, heat-treated alloy steel spherical bearings
- Extended Length: 29.83"
- Compressed Length: 18.46"
- Top Mount: Eyelet
- Bottom Mount: Eyelet
Fitment
Ford F-250 Super Duty (1999–2016) – 4WD – Rear
- Fits 0"–1.5" lift
Ford F-350 Super Duty (1999–2016) – 4WD – Rear
- Fits 0"–1.5" lift (most applications)
- Fits 2.5"–4" lift (2012–2013, 2016 models)
Ford F-450 Super Duty (2005–2016) – Rear
- Fits 4.5"–5.5" lift (most applications)
- Fits 1.5"–2.5" lift (2010, 2012, 2016 models)
Ford F-550 Super Duty (2005–2016) – Rear
- Fits 4.5"–5.5" lift
Installation
- Estimated Install Time: 1–2 hours
- Difficulty Level: Easy to Moderate
- Tools Required: Basic hand tools
- Hardware: Typically reuses factory mounting hardware unless otherwise specified
Notes
- Designed for stock and lifted applications
- Sold individually unless otherwise noted
- External reservoir requires proper routing and mounting
- Always verify fitment before purchase
Built Right. Backed Right.
Our crew’s on call Monday–Friday, 9–5 EST. Hit us up at 865-983-5004 — real support, done right.
Why Fox Shocks
Fox shocks are well-regarded in the off-road and performance world because they combine durability, advanced damping technology, and customization options that suit a wide range of vehicles and driving styles. For 4WD trucks, the “best” Fox shocks depend on how you actually use the truck — daily driving, towing, trail riding, or hardcore off-road.
Fox Shocks FAQ's
Should I Get 2.0 or 2.5 Shocks
Choose Fox 2.0 if:
You prioritize a smoother daily ride.
You stick to moderate trails and lighter off-road use.
Budget-friendly performance is key.
Choose Fox 2.5 if:
You demand more from your suspension—like aggressive off-roading, towing, or extended high-speed use.
You need better heat management and durability.
You don’t mind paying a bit more for enhanced performance and longevity.
Why Monotube Shocks Excel on Lifted Trucks
Handles Added Unsprung Weight – Larger wheels/tires from a lift add rotational mass and stress to your suspension. Monotube designs have better damping control to keep those tires planted.
Better Heat Dissipation – The single-tube design allows oil and gas to cool more efficiently, preventing fade during towing, off-roading, or long highway runs.
More Precise Handling – They respond faster to suspension movement, which is critical when correcting for body roll in a taller truck.
Will Better Shocks Improve Ride Quality
Tightening Up a Floaty Vehicle
If your truck feels like it’s “floating” or wandering at highway speeds, new shocks will firm up the suspension, improve steering response, and keep the body from rolling excessively in turns.
This doesn’t necessarily make the ride softer — it makes it more controlled.
Reducing Harsh Bouncing & Jarring
If you’re feeling hard bounce after hitting a bump (especially front or rear “pogo stick” motion), your shocks likely have lost rebound damping.
New shocks restore that damping, keeping your tires on the ground and absorbing energy before it reaches you.
Why Measure Shocks and Lift Height
1. Improved Ride Comfort
Matching the right shocks to your truck’s lift height enhances ride comfort. Ill-fitting shocks can cause a harsh, bumpy ride and limit suspension travel.
2. Better Handling & Control
Shocks sized for your lift height improve steering stability, cornering, and overall control — especially on rough terrain or with larger tires.
3. Increased Safety
The right shocks keep your tires in consistent contact with the ground, reducing the risk of skids, loss of control, or suspension component damage.
4. Greater Durability
When shocks operate within their intended range, they last longer and protect other suspension parts from premature wear.
5. Optimal Performance
A well-matched suspension setup ensures your truck performs at its best, whether you’re off-roading, towing, hauling, or commuting daily.