Frequently Asked Questions

How does the Greasecar system work?

The Greasecar system is a two tank fuel system. The vehicles existing diesel tank and filter will supply diesel fuel to the engine at start up and shut down. After start up radiator fluid will transfer heat from the engine to the heat exchangers in the Greasecar fuel system. These heat exchangers will heat the vegetable oil in the fuel filter, lines and fuel tank. The heat will reduce the viscosity of vegetable oil so that it is similar to diesel and can be injected into the engine properly. When the vehicle is being shut down for a period long enough for the fuel to cool the vegetable oil must be purged from the fuel system and replaced with diesel for the next start up. Purging generally takes around 30 seconds and can be done while driving with the push of the button on you Greasecar controls.

Do you have less power with a Greasecar system?

There have been no complaints of power loss with converted vehicles. Some customers claim to notice smoother acceleration when running vegetable oil. May vary depending on vehicle.

Is there added engine wear using a Greasecar fuel system?

No. Studies show that vegetable oil has superior lubrication and detergent values over conventional diesel fuel. Examination of engines running with the Greasecar system have shown dramatic reductions of carbon deposits over petro diesel in the engines studied.

Is there any extra maintenance to be done on a Greasecar?

Greasecars require only routine filter maintenance; commonly available filter under $10 for replacement. Filter replacement intervals depend on how clean oil is before it is poured into the fuel tank.

What kind of fuel economy (miles per gallon) do you get using a greasecar fuel system?

There should be no difference in fuel economy between diesel and vegetable oil. You will receive the high efficiency of a diesel engine on either fuel. (diesel engines are generally 40% more efficient than their gasoline counter parts)

Will a Greasecar fuel system reduce emissions?

Yes. There is no sulfur content in vegetable oil which eliminates the first major carcinogen associated with diesel fuel. Vegetable oil plants absorb more carbon dioxide from the air during their growing cycle than is released when the oil is burned, this means that vegetable oil does not produce excess carbon dioxide in the atmosphere (this is referred to as carbon neutral). Due to a slightly cooler burn some studies have shown NOX reductions when burning vegetable oil. More studies are underway and results will vary depending on engine and tuning. As a sulfur free, bio-mass fuel vegetable oil emissions are less harmful to the environment and less toxic to people and animals.

Will a Greasecar work in a cold climate?

Yes. The Greasecar system is engineered to perform in any climate, requiring only slightly longer warm-up times in extreme cold. Greasecar modified vehicles are used daily in temperatures below -30F.

Where do you get your vegetable oil?

Most Greasecar users fuel their vehicles with filtered frying oil that is collected from local restaurants. Most restaurants are happy to give their oil away as the generally have to pay disposal fees.

What vehicles do you recommend for conversion?

Our standard systems are designed to work with many diesel passenger vehicles and pickup trucks (custom kits available for larger applications). The most common diesel passenger vehicles in the US are made by Volkswagen and Mercedes. Chevy, Ford, GMC and Dodge all have diesel options on most of their larger pickup trucks.

Search for your application or view conversion candidates with the application search on our conversion kit pages.

How much work is involved in installing a kit?

The Greasecar conversion kit is designed for a do-it-yourself installation. Some vehicles will be more complicated than others, if you are concerned about your ability to successfully install the product, we can put you in contact with an installation specialist. To learn more about the conversion process, consider purchasing our step-by-step installation DVD.

What if you can't find vegetable oil? Can you still use your Greasecar?

Greasecars are dual-fuel vehicles; The existing diesel circuit is left in place. The engine is started and shut down with diesel fuel and can operate using the diesel tank at any time.

Can I use any type of vegetable oil?

Yes, any type of vegetable oil will work in your Greasecar, including hydrogenated oils. As long as the oil is filtered and free from water, bacterial and chemical contamination, it can be burned in a Greasecar.

Will the Greasecar system work with TDI vehicles?

The Greasecar system has been installed in hundreds of new VW TDIs some of which have logged more than 100,000 miles since conversion and no problems have been reported.

Are there significant differences between the Greasecar system and other systems on the market?

Yes, the Greasecar system has been developed to offer more reliable operation and assembled from the highest quality materials and components. The Greasecar system has been installed in thousands of vehicles and logged millions of miles, we have been in research since 1998 giving us unmatched expertise in development, research, design and manufacture capabilities. Features include tig welded aluminum tanks, 10 micron heated filter, QuickFlush in under 1 minute, open return circuit in diesel function, recirclation in veg function and our unique purge feature. For more detailed comparisons, please call 413-534-0013 or email .

What should I avoid when securing an oil source?

Avoid sources that rinse their fryers with water. While water will settle out of oil, a source containing water will require more attention and create contamination risks. It is also wise to avoid unsecure outdoor containers, as they are more likely to contain water and bacteria contamination. Water in your fuel can ruin your injection system!!

What type of restaurants tend to have the best oil?

Asian food restaurants and bar & grilles tend to use pure canola or soy oil which has a lower gel point and will be easier to collect and filter. As a basic rule of thumb, higher quality restaurants will use higher quality oil; most fast food restaurants use hydrogenated oil.

Will oil go bad?

Vegetable oil is a compostable material and will go rancid if exposed to the elements or subject to bacterial contamination. Filtering and storing your oil in a sealed container in a cool place will extend its life. There are additives called biocides that can be mixed with the oil to prevent bacteria from growing.

What does the "backflush" do?

Our back flush, or "purge" feature directs return fuel from the injection system into the vegetable oil circuit at shutdown while introducing diesel back into the injection system. This enables the injection system to be purged of vegetable oil in a very short period of time while priming unheated lines in the engine compartment with diesel. This feature can also be used to bleed air out of fuel lines and is done with a push of a button on your dash without the need to stop the vehicle and open the hood.

Can I modify my existing diesel tank to be used with vegetable oil?

Theoretically this is possible, although modification of a existing tank is not something Greasecar offers a system for. Greasecar does not offer such a system for numerous reasons, including legality of modifying a DOT certified tank, difficulty and reliability of installation, as well as other complications we have learned over the years.

Can I purchase a kit minus the tank? What about custom tanks?

Tankless kits are only available by special order. We always recommend a complete kit to ensure a successful conversion.  Custom tanks can be built to order at an additional cost.

Will adding a Greasecar Vegetable Fuel System void my vehicles warranty?

This seems to vary on a case to case basis and should be discussed with the dealer you have warranty coverage with. Generally we have found that the addition of a conversion system will, at the most, void coverage of fuel system components only.

Is this Biodiesel?

No. Biodiesel is a chemically engineered fuel, including vegetable oil, petroleum diesel, catalyst chemicals and some form of ester alcohols. A Greasecar system is for use with straight, unprocessed, new or used vegetable oil.