Why Using Fuel Ox® with Combustion Catalyst Does Not Breach an Engine Warranty

If you’ve ever been told that using a fuel additive could void your engine’s warranty, you’re not alone. But if that additive is Fuel Ox® with Combustion Catalyst, not only is that claim incorrect, it’s potentially unlawful. 

Trusted by the U.S. Military, global fleets, and equipment manufacturers for over four decades, our Fuel Ox® with Combustion Catalyst additive is one of the most rigorously tested, safest, and most effective fuel treatments on the market. Here’s why using it will not breach your engine warranty, and why it may actually extend engine life and reduce operating costs.

Decades of Proven Safety and OEM Compatibility

Fuel Ox® with Combustion Catalyst was originally developed and patented at Bell Labs in the early 1980s to protect bulk diesel fuel used by AT&T and the U.S. Military. Since then, it’s been trusted by fleets operating Caterpillar, Cummins, Komatsu, Peterbilt, Volvo, and nearly every major engine manufacturer. For over 40 years, the additive has maintained an unblemished safety record across millions of gallons of diesel.

We hold a multi-million-dollar product liability insurance policy, and in over twelve years of operation, we have never once had to pay out a claim. That’s because no documented case of engine damage from Fuel Ox® with Combustion Catalyst exists.

The Warranty Myth: What the Law Actually Says

Some field reps continue to claim that any fuel additive voids an engine warranty. This claim isn’t just misleading, it often runs afoul of U.S. law. Under the Magnuson-Moss Warranty Act, manufacturers cannot deny warranty coverage simply because an aftermarket product was used.

The law requires that they must prove that the additive directly caused the failure in question. Simply finding a fuel additive in the tank is not sufficient reason to void a warranty, and suggesting otherwise may be considered deceptive trade practice or commercial disparagement.

Four Common Grounds for Warranty Denial and Why Fuel Ox w/ CC Passes Every Test

1. Does Not Alter ASTM D-975 Fuel Specifications

Most OEMs require diesel fuel to meet the ASTM D-975 standard. Additives that push sulfur levels, viscosity, or lubricity outside of spec are red flags.

Fuel Ox® with Combustion Catalyst, however, is treated at a 1:10,000 ratio, a tiny dosage that does not affect key fuel parameters. Lab testing has confirmed that treated diesel remains chemically indistinguishable from untreated diesel, except it burns cleaner.

2. Prevents Harm, Doesn’t Cause It

Some low-quality additives contain metals or unrefined organics that leave ash or form acids, damaging injectors, EGR valves, and fuel tanks. Fuel Ox® with Combustion Catalyst does the opposite. Its:

• Organometallic combustion catalyst promotes more complete burn and reduces soot
• Detergents keep valves and injectors clean
• Corrosion inhibitors protect fuel systems from rust and acid

Field data consistently shows longer injector life, cleaner EGR systems, and lower soot in engine oil.

3. Supports Emissions Hardware, Doesn’t Interfere

High-ash additives can plug diesel particulate filters (DPFs), and some compounds can poison SCR (Selective Catalytic Reduction) systems. But Fuel Ox® with Combustion Catalyst is engineered to enhance emissions performance, not degrade it. By enabling cleaner combustion, the additive:

• Reduces soot emissions by up to 70%
• Decreases DPF regens by over 60%
• Lowers DEF (Diesel Exhaust Fluid) usage by 15–20%

These improvements protect components like DPFs, EGR coolers, and sensors, extending their lifespan.

4. Extensive Third-Party Validation

Fuel Ox® with Combustion Catalyst isn’t just trusted, it’s validated:

• Detroit Diesel / Rolls Royce / MTU test results
• Independent fleet trials
• University dynamometer studies
• EPA registration and international patents

Several OEM dealers have even issued “approved for use” or “no harm” letters based on their own evaluations.

What If an OEM Claims Otherwise?

If a manufacturer representative tells you Fuel Ox® with Combustion Catalyst will void your warranty:

1. Ask for their name, company, and exact wording
2. Document the conversation
3. Email info@fuelox.com

Fuel Ox will provide supporting documentation and, if necessary, engage the OEM directly on your behalf.

Bottom Line: Fuel Ox® with Combustion Catalyst Does Not Void Your Warranty

Fuel Ox® with Combustion Catalyst:

• Keeps fuel within spec (ASTM D-975)
• Protects engines and emissions systems
• Reduces maintenance costs and downtime
• Has never caused a single warranty issue in decades
• Is protected by federal warranty law

This is not just about legality, it’s about performance, protection, and peace of mind. Far from jeopardizing your warranty, Fuel Ox® with Combustion Catalyst supports your engine’s longevity and your bottom line. Made in the USA. Trusted worldwide. For more information or warranty documentation, please contact us.