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Propane Tank under car

Duke Energy uses this type of vehicle in their fleet. I would call Duke and they would have the answer to the tank under the car.

Duke Energy would have the answer. Give the local Electric Company.

These are not-so-common, but have been around for a while. I had a friend back in the 80’s that drove a former police car set-up to run on Propane. It had an LP tank under the car, and the gauge was set-up to read the available level of LP. Of course, he had to fill-up at a U-Haul outlet.

CNG systems are very common in South America and are also used in city vehicles in the States. The caller with the truck with a CNG system may get a refill from the city.

Engines on CNG run pretty good, maybe a little warmer than with regular gas and there’s also some more wear off since CNG lacks the lubrication that gas supplies.

The systems are safe provided that they’re designed for this purpose but regular “grill” propane tank are not designed for the pressure used to refill vehicle CNG tanks. The tanks can be made of steel or a lighter glass fiber kind of material.


Another contact Volkswagen Europe. My freind in Italy has a VW Passat. It has the dual fuel system. It came from the dealer so equipped. It is his second or third Passat. It is a wagon. Where the spare is, they take out the spare and put a donut storage tank. I have driven under all sorts of conditions with him…really economical using CNG…you really can’t tell difference in fuels. There was no problem finding the CNG at regular gas station in most of Italy. Fill is as descrided on the radio…standard fill connector mechanism. Warning, a concern…for every 3-5 CNG fills, you must do a gasoline fill. It seems CNG dries out the gaskets. Don’t know if this is still the case. I’m not a mechanic.

careful, this is a CNG system. Dont try to put propane in it. I don’t think it would work very well with LPG in there. there are lots of CNG & LPG systems out there. Ford did a nice job working with alternate fuel systems like this. they even have OEM systems. the bad part is that there are very few CNG fill stations available for public use. check with the city, maybe they are using it on some of there trucks.

The key to the mystery is the Carfax history of “Fleet Vehicle” What type of companies have large fleets of work trucks and similar vehicles along with a cheap, reliable cource of natural gas? In a previous life this Ford was mist likely a Gas Company service vehicle…

I worked for the upfitter that installed these systems for Ford. This was a factory approved installation sold through certain Ford dealers. The tank is either a 3000 or 3600 PSI Compressed Natural Gas tank with a kevlar wrap, VERY STRONG, so no worrys about an explosion. CNG can be cost effective but actually has less energy density than gasoline, it is cleaner to burn and doesn’t have the byproducts that dirty the oil. These were originally sold to fleets. The same company that built that system also provided systems for the Contour also in a “bi-fuel”(gasoline & CNG) configuration, as well as a CNG only pickup, also they produced an LPG bi-fuel pickup. Here’s the bad news the tanks are only good for 12 years, and then must be replaced, the expiration date can be found on the tank, if its expired it should not be used, drive it until its empty then don’t use it until the tank gets replaced! These systems were built by GFI from Kitchener, Ontario.


This sounds more like CNG than LPG. The best source for advice would be Piedmont Natural Gas, if the inqiry is coming from Charlotte. Another resource is the American Gas Association website Gas utilities often operate their light trucks on CNG and the caller’s truck could have originally been converted to dual fuel by a utility.

Hello.Been doing CNG for 22 yrs.First you need to figure out if your system is CNG or LPG.If as you have said the GFI and CNG is the lable on the system then it is CNG.The cylinder is not a tank.Cylinders hold compresed gas and tanks hold liquids.They had three systems.First was the 2400lbs system.Steel cylinders that require re-cert testing every five years.Next came the 3000lbs alum fiberglass wraped.10 years and replace.Ford and chey teamed with GFI to make a dedicated system only runs on CNG.Others used the duel fuel like what you have said is on your truck.This system was the most popular due to the use of both fuels.The system shuts off the fuel injectors and allows CNG to enter the throttle body thru a metered air mixer.I would not use this system until it is checked for cylinder exp date and if that is good you need to fill the system and check for leaks.CNG is the safest fuel you can use over gasoline or LPG.The price is generally 1/2 of Gasoline per the thermal unit and mileage is the same as gasoline.The 3600lbs system was used by Ford and Chevy.Chevy got away from CNG due to stupid people using the trucks to haul used batteries.The acid leaked on the cylinders under the bed.After being exposed the the acid the cylinders became compromised and upon filling to pressure there was a failure.Lawsuits and Chevy got away from the CNG conversion.Hope this helps.S-King

This is a very interesting subject. I have researched this thoroughly and found that Natural gas is a very clean fuel, cleaner than propane. And since it isn’t a liquid you don’t get the freeze up problems you can get with propane. The problem is getting it in your car. I have a natural gas stove in my house and I could buy an electric pump that will compress that from 4 lbs to 600 lbs. Otherwise you would have to find re-fueling stations use this link also the USDA has a site that is very informational. Natural gas runs very efficiently in a cold engine whereas a gasoline engine needs to be choked to start CNG does not. Also there are TAX benefits. 1. in my state I do not have to pay road tax on CNG 2. There are many tax deductions to use alternative fuels. if you want you can email me at Run in CNG mode as much as you can. If I could buy an equivalent or better fuel at 85 cents a gallon I would.