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  • What is an FFS Fuel Optimizer?
  • It is an aftermarket, onboard mini-refinery for all class 8 trucks, buses, RVs, farm equipment, and smaller trucks.
  • FFS systems use the power of cavitation to ultra-refine diesel and biodiesel. This patented process homogenizes all fuel constituents, atomizing entrained and/or free water clusters, pulverizing contaminants, and returning the fuel to its original refinery state or better.
  • The system conditions and cleans your fuel tanks as you use it. May eliminate the need for algaecides and additives.
  • What are the benefits of using an FFS onboard system?
  • Optimized combustion achieves better performance, lower fuel consumption, and reduced emissions.
  • The system produces an optimized fuel which results in enhanced combustion consistently across all cylinders. This in turn results in a quieter, smoother-running engine operating at lower engine temperatures, with more power and torque, and smoother acceleration and deceleration.
  • Drivers report less emissions-related down time, such as faulty EGR or DPF cleanings required, due to cleaner burning fuel.
  • How long does installation take?
  • Around two hours with basic mechanic skills.
  • The system requires no engine or electronic control module (ECM) modification, easily connecting to fuel tank or fuel lines and 12VDC. (The X-1 has a small indicator display box run to the cab.) Installation time is normally two hours, but may be longer depending on truck specifics and install location.
  • What does an FFS system cost and is financing available?
  • Please call or contact for pricing and options, and yes, financing is available.
  • Price can vary depending on the truck style and mounting configuration desired or required. Call or contact us for pricing and options currently available. Financing options are also available. Request for Quotation.
  • Are FFS systems approved by government regulators?
  • Yes. The EPA has tested and considers them a filter: diesel in, diesel out.
  • FFS systems ultra-refine diesel fuel, which remains diesel fuel after processing. Testing at the Michigan EPA facility confirmed this. Considered a filter, our systems require no special approvals or regulation.
  • What are the economic benefits of operating an FFS fuel optimizer?
  • Fuel savings of up to 20% plus many intangible savings, with ROI often less than a year.
  • Annual fuel savings up to 20% or more depending on driving style, engine model and condition. Over 750,000 miles of real-world tests and usage confirm 20% savings is achievable on a regular basis. Other economic benefits include a cleaner, quieter, smoother-running engine leading to longer engine life, potentially fewer oil changes, fuel filters, DPF regen cycles and/or fluid, etc.


  • Will I notice performance improvement right away?
  • Most drivers immediately notice a quieter engine with less vibration and more power.
  • Mileage improvement begins to show during the first several hundred miles, as the engine is cleaned and the ECR adjusts to better fuel. It continues to improve, with incremental increases for up to six months after installation.
  • Drivers set their radios a notch or more lower. Progressive shifting can be achieved at lower RPMs without compromising speed and performance. Lower exhaust, oil and coolant temps result in less engine strain while fewer clutch fan engagements save you more fuel. In most cases, drivers downshift less often and can climb grades a gear higher.
  • Will my fuel savings start immediately?
  • Yes, though it will gradually improve as your engine is cleaned and your ECM adjusts to better fuel.
  • FFS recommends an early oil change as much of those carbon and coke deposits end up in your oil. Fuel savings continue to improve as your ECM adjusts to better fuel and a cleaner engine.
  • Change your oil after 3-5000 miles to get rid of the carbon and coke sludge. Resume normal oil changes after the initial purge.
  • Does the FFS technology change anything on the engine?
  • No engine modifications are required.
  • FFS fuel optimizers do not interfere in any way with the engine integrity or its normal operation. They simply deliver better fuel to the engine, resulting in improved combustion. FFS systems can be shut off, returning to unprocessed fuel at any time.
  • What effect will my FFS system have on the durability of my engine?
  • Because your engine burns optimized fuel it will run better and last longer.
  • Operation of FFS systems has no negative effects on engine wear rates and durability. Just the opposite occurs, because burning optimized fuel actually cleans engine internals while driving. Independent tests confirm significant reductions in oil soot and wear metals, and carbon and coke deposits are eliminated without detergents. This can extend engine life and oil change intervals.
  • Can I transfer my FFS system to another truck?
  • Yes, you can remove the system and install it on a different vehicle at any time.
  • Your FFS fuel optimizer can absolutely be transferred to another vehicle. The system has been engineered to US DOT and OEM standards and is lifecycle tested for 15+ years. It was designed to be transferable for continued profits.
  • Are maintenance schedules or engine life affected by installation of FFS technology?
  • General maintenance and service cycles remain the same as the base diesel engine.
  • Because FFS systems produce better combustion and a cleaner engine with less emissions, you may find that oil changes can be less frequent, fuel filters last longer, and regen cycles are less frequent with less DEF fluid consumption.
  • How do I order an FFS system and how soon will it be available?
  • Contact FFS via email or phone and expect delivery within a month.
  • Simply email a Request for Quotation, supplying your vehicle style and mounting configuration. You can expect delivery within one month of order placement.


  • Will my FFS system affect my engine’s manufacturer warranties?
  • No. Engine manufacturers must honor their warranties, and FFS will honor its fuel optimization system warranties.
  • FFS systems do not modify your engine in any way. FFS warranties system components for two years after installation. Industry documentation and regulations cite the following in regard to the effects of an approved aftermarket technology on OEM warranties:
    • Magnuson-Moss Warranty Act of 1975 says the consumer has the freedom to choose aftermarket parts and upgrades without having the OEM warranty voided.
    • FFS warrants that no engine damage will occur as a direct result of using an FFS system.
    • The Federal Trade Commission (FTC) issued a Consumer Alert in January 2011 confirming that it is in fact illegal to void warranties or deny coverage for the use of an aftermarket part.
  • How long can I expect my FFS system to last beyond the FFS warranty?
  • Many years. Our pump is cycle-tested to 1.5 million miles and beyond.
  • The only moving part in an FFS system is its pump. (The X-1 also has interim fuel tank floats.) Cycle bench tests of a pump are ongoing, having surpassed 1.5 million equivalent miles with the pump still going strong. Given proper care, your FFS system just may outlive your vehicle and be transferred to another vehicle.

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Fierce Fuel Systems is dedicated to putting your hard earned $ in your bank, not in your tank.

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