Letter Re: A Little Insight on Diesel Engines

JWR:
I second the recommendations in Gary’s letter wholeheartedly. My survival vehicle of choice is a 1997 Dodge Ram 2500 with faded paint and some cosmetic body damage from its former life as a work truck. Now it is known as the “McDodge”, thanks to the conversion kit from Greasecar.com which has been running in it for about two years and 12,000 greasy miles. I did extensive research when I was deciding what vehicle to purchase and came down to either an 1980s model Mercedes diesel (which have legendary reliability) or the 1994-1998 Dodge diesel with the also-legendary 5.9L Cummins engine. As expressed by Gary, these were originally a heavy equipment engine, Dodge just decided to wrap a truck around it. I acquired mine in 2008 with 222,000 miles on it for $4,000. It’s not pretty but the drive train is in great shape. The engine is totally mechanical, no microchips whatsoever. It will withstand any EMP event that doesn’t physically destroy the truck. I have since learned that the automatic transmission does have chips, so perhaps the whole system is not as bulletproof as I thought. Here in farming country in rural Texas, these trucks are ubiquitous, don’t stand out at all, and the mechanics know how to work on them. Every time I drive into a city I get some interesting looks, however.

Let me take a minute to highly recommend the Greasecar conversion kit. It came with all necessary components, and I had it professionally installed for about $1,000. The kit was about $2,000. Yes, I have now spent quite a bit more on the truck than I paid for it initially. For those who are not familiar with Waste Vegetable Oil/Straight Vegetable Oil (WVO/SVO), it’s a close cousin to biodiesel but without the chemistry. You convert the truck once instead of converting each batch of fuel. The conversion kit adds a secondary 40-gallon fuel tank in the cargo bed, so if the factory tank is full of diesel I have 70 gallons of fuel on board total. Very comforting considering the truck gets around 18-20 mpg on the highway. Diesels have a higher thermal efficiency due to the much higher compression ration than gas engines (around 16:1 for the Cummins 5.9L). Other companies also sell quality conversion kits and parts (the Frybrid company comes to mind). I assure you that the ’94-’98 Dodge/Cummins trucks like oil just fine. The power and mileage are essentially unchanged, I’ve never been able to notice any difference. About 3-to-5 minutes after you start the truck on diesel, the controller senses that the engine temperature is adequate for running oil and all you hear is a very small click as the two solenoid valves change over. I have experimented quite a bit and I find the engine doesn’t mind changing over at temperatures as low as 120°F if you’re driving on the back roads as I am. If you need power for merging on to a highway I would wait until about 140 degrees or the engine will complain and you’ll get smoke.

Since late 2008 when fuel prices went back down, I have been burning diesel and stockpiling the oil. I now have about 800 gallons stored in 330-gallon IBC “cube” containers. It’s my form of “oil futures”. The oil is reported to last for numerous years stored like that, but I can’t say from firsthand experience. All of my oil is recycled fryer grease that goes through an extensive multiple step filtering and settling process. By the time it goes into the tank it’s crystal clear and golden. It definitely does smell like whatever was fried in it, and the older oil has a noticeable tang of rancidity, but the truck digests it just fine. In fact, the fuel tank itself is also heated so theoretically one could actually burn solid fat like lard or tallow in it. Animal fats, being more saturated, actually store better and oxidize less. Personally I haven’t tried it due to the difficulty in filtering and setting fats that would be solid at normal temperatures.

Back in 2008 I was already doing my disaster planning and R&D, well before I had heard of this site or read any of JWR‘s books. I arrived at the Dodge/Cummins truck in combination with WVO/SVO as the best solution for durability, survivability, and sustainability. I have a couple hundred acres of farmland and I am experimenting with peanuts and sunflowers to see if it will be feasible to grow my own fuel. Both of my tractors are diesel, but I have not tried running them with oil or an oil blend. I suspect I could easily run a 50/50 blend in any weather and probably 100% oil in the Texas summer with no problems. By my calculations, around 20 acres should suffice to grow a year’s worth of fuel for all the equipment, unless I’m using the oil to generate electricity.

In addition, the conversion is very stealthy. I did not apply the large “Greasecar Vegetable Fuel Systems” rear window logo graphic that came with the kit. Unless you look very close the fuel tank looks much like a tool box or one of the bed tanks common around here for fueling heavy equipment. Of course, if you get behind me on the highway there’s no mistaking the French Fries smell. – Stew in Texas