Does FuelMarble work if my vehicle already uses coolant additives?

Yes, and the laboratory data confirms it. Professor Watanabe's research at Kurume Institute of Technology tested FuelMarble specifically inside a 30% coolant additive solution, the same concentration used in most commercial trucks and buses. Two tests were run. Test 1 (pH stability): pH remained completely stable. FuelMarble does not react with or cancel out existing coolant additives. Test 2 (surface tension): FuelMarble reduced surface tension by a further 2% on top of what the coolant additive was already achieving, measured across 25–70°C. Because FuelMarble works physically (not chemically) it adds its effect on top of whatever your existing additives are already doing. Notably, virtually all vehicles in Japan run coolant additives as standard, meaning the real-world performance data (including the Yamanashi Kotsu bus trial) was collected with coolant additives already present in the system. The results are not from pure-water conditions.

Which Vehicles It Works On

Which vehicles is FuelMarble compatible with?

Q: Which vehicles are compatible with FuelMarble?

FuelMarble is compatible with any vehicle that has a coolant reservoir connected to an internal combustion engine: petrol and diesel passenger cars, SUVs, motorcycles, delivery vans, haulage trucks, agricultural machinery, generators, boilers, and marine vessels. Choose FuelMarble S for passenger vehicles and light commercial; choose FuelMarble L (or multiples) for heavier vehicles.

FuelMarble works in any vehicle with a coolant reservoir connected to an internal combustion engine, petrol or diesel. This is the compatibility and sizing companion to our overview of how FuelMarble's coolant technology works: which vehicle classes it fits, how many units by weight, and the independent coolant-system safety data.

Compatibility

Compatible vehicle types

FuelMarble works in any vehicle with a coolant reservoir connected to an internal combustion engine, petrol or diesel.

Personal Cars & Sedans

SUVs & MPVs

Buses & Coaches

Delivery Vans

Haulage Trucks

Agricultural Machinery

Marine Vessels

Unit sizing by vehicle weight

Vehicle Class	Example Models	Approx. GVWR	SKU	Units
Motorcycles & small cars	Honda Civic, Toyota Yaris, VW Polo	Under 1.5t (≈ under 3,360 lbs)	FuelMarble S	1
Family cars, SUVs & MPVs	Ford Focus, BMW 3 Series, Toyota RAV4	1.5–2t (≈ 3,360–4,480 lbs)	FuelMarble S	1
Large SUVs & pickup trucks	Land Rover Defender, Toyota Hilux	2–3t (≈ 4,480–6,720 lbs)	FuelMarble L	1
Light commercial vans	Ford Transit, Mercedes Sprinter, VW Crafter	3–4t (≈ 6,720–8,960 lbs)	FuelMarble L	1
Medium trucks	Isuzu NPR, MAN TGL, DAF LF	4–13t (≈ 8,960–29,120 lbs)	FuelMarble L	2
Heavy trucks & HGVs	Volvo FM, DAF XF, Scania R, MAN TGX	13t+ (≈ over 29,120 lbs)	FuelMarble L	3

GVWR (Gross Vehicle Weight Rating) figures are indicative; pound equivalents follow your region's ton. Multiple units share one coolant circuit. They do not require separate reservoirs.

FuelMarble S

Get FuelMarble S for cars and vans under 2 tonnes.

FuelMarble L

Get FuelMarble L for HGVs, buses, and commercial vehicles.

Running more than a handful of vehicles? See fleet-wide deployment for UK operators.

Coolant System Safety

Coolant System Safety & Compatibility

Independent laboratory testing confirms FuelMarble has no adverse effect on standard automotive coolant. PH stays neutral, viscosity is unchanged, and oxidation resistance doubles.

Tested in 30% ethylene glycol solution (standard automotive antifreeze concentration). Watanabe et al., SAE Japan 2008

Property	Result	Conclusion
pH	Peaks at 7.4 at 80°C	Neutral throughout 30–90°C operating range. No acidification risk.
Viscosity change	< 0.7% over 14 days	Negligible. No impact on water pump performance.
ORP (Oxidation Resistance)	Doubles from 345 mV → 692 mV	Treated coolant actively resists oxidation and scale. Extends cooling system lifespan.
Surface tension	Reduced ~2% (20–70°C)	Sustained reduction across full operating temperature range.
Heavy metals	None leachable	Inert sintered glass. No solvents.

Compatible with standard coolant inhibitors. For a full explanation of how FuelMarble differs chemically from fuel additives (including why it carries zero DPF risk) see our dedicated guide.

Lab Research. Prof. Watanabe, Kurume Institute of Technology

What if my fleet already uses coolant additives?

FuelMarble delivers 7–10% fuel efficiency improvement even when installed in a coolant system that already contains liquid coolant additives. No reduction in performance. No chemical conflict.

Test 1, pH Stability

FuelMarble was tested inside a 30% coolant solution, the same concentration used in most commercial trucks and buses. pH remained stable throughout. The coolant chemistry was not disrupted. FuelMarble does not interfere with existing coolant additives.

Test 2. Surface Tension

FuelMarble was tested inside 30% coolant solution across 25–70°C. Surface tension dropped by a further 2% compared to coolant alone, confirming FuelMarble's core mechanism continues to work even with coolant additives already present.

Japan context: Virtually all vehicles in Japan already run coolant additives as standard. This means the performance data, including the Yamanashi Kotsu bus trial results. Was collected under real-world conditions with coolant additives already in the system. The results are not from pure-water conditions. FuelMarble's verified 7–10% improvement is what you can expect on top of your existing additives, not instead of them.

Still weighing it up? See answers to common compatibility questions, including winter performance and how it affects horsepower.

FAQ

Frequently Asked Questions

Find the right unit for your vehicle

FuelMarble S FuelMarble L