Natural-gas cars sell only in tiny numbers to individual retail buyers, although they have found some traction with fleets that have ready access to the fuel.

Now, those fleet buyers will get another choice--one that happens to be the best-selling vehicle in the U.S.

The 2016 Ford F-150 will be offered with a gaseous-fuel prep package, allowing it to run on compressed natural gas (CNG) or propane.

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Ford says the F-150 will be the only half-ton truck available that can run on these fuels.

The kit can only be ordered on models equipped with the 5.0-liter V-8 engine.

Towing capacity is unchanged compared to the gasoline version, while payload capacity is the same minus the weight of extra equipment for the CNG/propane fuel system.

2016 Ford F-150 CNG conversion

2016 Ford F-150 CNG conversion

Trucks are prepped at the factory with upgraded intake and exhaust valves and valve seats, at an option cost to the buyer of $315.

Trucks are then shipped to Ford-approved shops to complete the conversion, which involves adding fuel tanks and lines for CNG or propane, as well as special fuel injectors.

These conversions cost approximately $7,500 to $9,500, depending on fuel-tank capacity.

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Ford partners with four "Qualified Vehicle Modifiers" to perform F-150 natural gas or propane conversions.

Altech-Eco based in Asheville, North Carolina, Westport of Dallas, Texas, and Venchurs Vehicle Systems of Adrian, Michigan, all perform CNG conversions.

In addition, IMPCO Automotive based in Sterling Heights, Michigan performs both CNG and propane conversions.

2016 Ford F-150

2016 Ford F-150

Ford maintains the factory warranty for converted vehicles, but the modifiers are responsible for covering any parts they install.

While converting a truck to run on CNG adds cost, the fuel is typically cheaper than gasoline.

The average national price was $2.11 per gallon of gasoline equivalent as of April 30, compared to $2.58 per gallon for regular unleaded and $2.81 per gallon for diesel.

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However, natural gas only makes sense for fleet operators that can secure their own supplies of fuel, as there are only about 500 natural-gas fueling stations in the U.S. that are open to the public.

Ford last offered a natural-gas conversion on 2014 F-150 models equipped with the 3.7-liter V-6.

It skipped 2015, the introductory year for the current-generation F-150.

2016 Ford F-150

2016 Ford F-150

With the 2016 F-150, Ford will offer eight models with the gaseous-fuel prep option from the factory.

Those include the F-250 and F-350 Super Duty pickups as well as the light-duty F-150, along with larger chassis-cab trucks, and the Transit and Transit Connect vans.

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Ford sold 16,821 vehicles with this option in 2014--representing a fifth straight year of record sales.

It it expects 2015 to be a record year as well in what appears to be a growing niche for the Dearborn carmaker.


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