Introduction: Building a Long Travel Suspension System

For off-road enthusiasts and overland explorers, a long travel suspension system is one of the most effective upgrades for improving vehicle performance on rough terrain. By increasing wheel articulation and providing more controlled damping, these systems allow drivers to maintain stability, comfort, and traction when the pavement ends. The core of any long travel setup lies in the shock absorbers—and the brand you choose directly affects ride quality, durability, and adjustability.

In this guide we examine the most respected names in long travel suspension components: Fox Racing Shox, King Shocks, and Bilstein. We also cover other noteworthy brands such as Icon Vehicle Dynamics and Radflo. Whether you drive a lifted truck, an SUV, or a dedicated off-road rig, understanding the strengths of each manufacturer will help you make an informed decision for your next build.

Fox Racing Shox: Technology and Tuning for Extreme Conditions

Fox Racing Shox has built a reputation on race-proven technology and constant innovation. Their long travel shocks are used in everything from trophy trucks to overland vehicles, and the brand offers a wide range of configurations for different applications.

Key Technologies

Fox’s patented Dual Speed Compression (DSC) adjuster allows fine-tuning of both high‑speed and low‑speed compression separately. This is critical for off-roaders who encounter both rocky crawling and high-speed desert runs. Other noteworthy technologies include the Internal Floating Piston (IFP) design that separates oil and nitrogen gas, preventing cavitation during extreme use.

  • DSC Adjustment: Enables precise damping changes for different terrains without swapping out valves or shims.
  • Bypass Shock Options: For maximum performance, Fox offers bypass shocks that provide progressive damping as the shock extends, ideal for high-speed desert racing.
  • Rebuildable and Serviceable: All Fox shocks can be serviced with readily available parts, extending service life when properly maintained.

For long travel systems, Fox offers the 2.0 Performance Series, the 2.5 Factory Series with DSC, and the 3.0 Factory Series for heavy-duty applications. The 2.5 DSC shocks are especially popular for full-size trucks and SUVs because they combine durability with tuning flexibility.

Many aftermarket long travel kits from companies like Baja Kits and Camburg pair Fox shocks as standard. This ecosystem of compatibility makes Fox a go-to choice for builders who want a proven, off‑the‑shelf solution.

External links: Fox Racing Shox Official Site

King Shocks: Precision Engineering for the Demanding Off-Roader

King Shocks is synonymous with high-end, race‑focused suspension. Their shocks are found on trophy trucks, PPIHC racers, and adventure builds that require extreme articulation and fade‑resistant performance.

Build Quality and Customization

King shocks are manufactured in the USA with a focus on tight tolerances. Each unit is assembled to order, allowing customers to choose spring rates, valving, shaft size (5/8”, 7/8”, or 1”), and even reservoir placement. This level of customization is rare among mass‑produced competitors.

  • Smooth Bore Housings: King uses a proprietary honing process to achieve a mirror‑like finish inside the shock body, reducing friction and wear.
  • High Temperature Seals: King’s seals are designed to survive sustained high heat from repeated hard impacts, a common failure point in lesser shocks.
  • Adjustable or Fixed: King offers both adjustable and non‑adjustable versions, with external bypass tubes available for advanced tuning.

Ideal Applications

King’s 2.5 and 3.0 coilovers and bypass shocks are favorites among desert racers and rock crawlers. Their ability to handle sustained high-speed abuse makes them a top pick for Baja‑style terrain. Long travel kits designed for King components often come pre‑valved for specific vehicle weights, but custom tuning is recommended for precise ride quality.

Because King builds each shock to order, lead times can be longer than off‑the‑shelf brands, but the result is a suspension that performs exactly as intended.

External links: King Shocks Official Site

Bilstein: German Engineering for Consistent Product Performance

Bilstein is one of the oldest names in shock absorption, and their monotube technology has been trusted by OEMs and aftermarket enthusiasts for decades. For long travel applications, Bilstein offers the 5100 series, 5160 series (with remote reservoir), and the high‑end 6112 coilovers.

Monotube Advantages

Bilstein’s monotube design places a floating piston at the bottom of the shock, separating oil from nitrogen. This allows for faster heat dissipation than twin‑tube designs, which is essential when repeatedly cycling a long travel suspension. Heat buildup causes oil viscosity to drop, leading to reduced damping—Bilstein excels at managing this issue.

  • Digressive Piston: Bilstein’s patented digressive piston provides firm damping at low shaft speeds (body roll, braking) and softer damping at high shaft speeds (sharp bumps), striking a balance between control and comfort.
  • Zinc-Plated Steel Body: Corrosion resistant and durable, even under extreme salt and mud exposure.
  • Wide Application: Bilstein covers many OEM replacement and lift applications, including coilover systems for Tacoma, Tundra, 4Runner, and Jeep models.

Long Travel Considerations

While Bilstein is not as customizable as Fox or King (limited valving options and no external bypass for most models), their price point is often lower, making them an excellent entry into long travel performance. The Bilstein 5160 remote reservoir shocks provide additional oil capacity and gas volume, reducing fade during prolonged use. For many overland builds, these are a cost‑effective compromise between street comfort and off‑road capability.

External links: Bilstein Official Site

Other Notable Brands in the Long Travel Space

Beyond the big three, several manufacturers offer quality long travel components that deserve attention. Each brings unique advantages depending on your vehicle and budget.

Icon Vehicle Dynamics

Icon is known for its RXT and VS series shocks, which feature internal bypass technology (called "Billet Aluminium Internal Piston" in some models) for progressive damping without external tubes. Icon shocks come pre‑valved for specific vehicles (e.g., Ford Super Duty, Toyota Tundra) and include adjustable compression. Their customer service and documented tuning guides make them popular among DIY installers.

Radflo

Radflo offers budget‑friendly shocks and coilovers without sacrificing quality. Their 2.0 and 2.5 series shocks use a similar monotube design and can be rebuilt. Radflo is a good choice for those building a long travel kit on a tighter budget or for lighter vehicles that don’t need the extreme heat capacity of Fox or King.

Sway‑A‑Way (SAW)

SAW is a veteran brand that produces coilovers with unique body styles and valving options. Their shocks are often used in desert racing and are made to order. SAW’s pricing is competitive, but lead times can be longer.

ADS (All Digital Suspension)

ADS shocks are hand‑built in the USA and offer extreme adjustability through their Digression Series. ADS uses a proprietary high‑flow piston design and is popular among serious racers who need maximum control. They are less common in mainstream builds but are worth noting for high‑horsepower off‑road projects.

Comparison: Fox vs. King vs. Bilstein vs. Others

The following table summarizes key differences to help you decide.

Feature Fox King Bilstein Icon/Radflo
Customization Options High (valving, DSC, bypass) Very High (made‑to‑order) Moderate (piston size, spring rate) Moderate (specific vehicle kits)
Heat Handling Excellent (large oil volume) Excellent (smooth bore, seals) Good (monotube) Good moderate
Adjustability DSC, bypass tubes External bypass, compression adjusters Digressive fixed valving (most models) Compression adjust (some models)
Price Range $$$$ $$$$$ $$ $$–$$$
Availability Widely available Made‑to‑order (longer lead) Readily available Good

This is a general guide. Your specific vehicle, weight, and terrain will shift the recommendation. For instance, a heavy overland rig on washboard roads may benefit from King’s custom valving, while a weekend trail truck might be perfectly happy with Bilstein 5160s.

Factors to Consider When Selecting Long Travel Components

Vehicle Weight and Intended Use

Total vehicle weight (curb + extra gear, bumpers, winch) directly affects spring rate and damping needs. A shock valved for a lightweight truck will overheat and bottom out on a heavy build. Always provide your vehicle’s actual weight (corner weights are best) to the shock manufacturer or tuner.

Travel and Cycle Life

Long travel shocks operate over a longer stroke than stock. This increases heat and internal pressure. Choose a shock with appropriate shaft diameter (2.0” for mild, 2.5” or 3.0” for aggressive) and consider reservoirs to add oil capacity. Fox and King both offer large reservoir options.

Maintenance Intervals

All high‑performance shocks require periodic rebuilds (every 20,000–30,000 miles or after severe use). Fox and King have extensive service networks; Bilstein is less rebuild‑friendly for many models. Factor in service costs when budgeting.

Warranty and Support

Fox offers a one‑year limited warranty. King offers a similar period. Bilstein’s warranty varies by series. Icon and Radflo also offer limited warranties. Customer support can vary; calling the manufacturer before purchase is recommended.

Installation Tips for Long Travel Shocks

Installing aftermarket long travel shocks is not as simple as a bolt‑on job in many cases. You may need new upper control arms (UCAs), shock hoops, and sometimes frame reinforcement. Always follow the kit manufacturer’s instructions. Here are a few general best practices:

  • Check shock length at full droop and full bump before installing to avoid binding.
  • Use proper torque specs for all mounting bolts—under‑torquing can cause bushing failure.
  • Purge air from the shock after installation by cycling the suspension several times with the reservoirs upright.
  • Set equal preload on coilovers (left vs right) to avoid vehicle lean.
  • After installation, check bump stop contact—long travel kits often require custom bump stops.

If you’re unsure, have a professional off‑road shop perform the installation and initial tuning. A poorly set‑up long travel system can be dangerous at speed.

Maintaining Your Long Travel Shocks

Shock maintenance extends lifespan and preserves performance. For Fox and King:

  • Clean shock shafts after every off‑road trip to prevent dirt from damaging seals.
  • Check nitrogen pressure annually (typically 150–200 psi). Low pressure causes cavitation.
  • Inspect for oil leaks around the shaft seal—early detection prevents internal damage.
  • Replace bushings and spherical bearings yearly if the vehicle sees frequent off‑road use.

Bilstein 5160 and 5100 shocks are generally non‑serviceable (most are sealed), so replacement is the only option when they fail. However, they are built to last many miles.

Conclusion: Matching the Brand to Your Build

Selecting long travel suspension components requires balancing performance, cost, and serviceability. Fox Racing Shox offers the best blend of advanced adjustability and widespread support for most popular vehicles. King Shocks deliver unmatched customization and heat management for extreme off‑road use, but come with a premium price and longer lead times. Bilstein provides a reliable, cost‑effective entry point for long travel systems, though with less adjustability.

For those on a moderate budget or building a lighter vehicle, Icon and Radflo are solid alternatives. Ultimately, the best brand is the one that matches your driving style, vehicle weight, and willingness to perform regular maintenance. Take the time to research your specific vehicle’s long travel kit options, and don’t hesitate to contact manufacturers directly for tuning advice. A well‑chosen suspension system transforms your off‑road experience—allowing you to confidently tackle terrain that once felt impossible.

External links: Fox Racing Shox | King Shocks | Bilstein