I do not believe all Jet fuel is #2 fuel. At work we have a 50 mega-watt generator powered by 2 Pratt & Whittney Air Craft engines (FT-4 & FT-11) if I remember correctly. These units run on straight kerosene for fuel ( this I know for sure ). I don't believe all Jets use this as fuel and I think there are different types, but I am not positive of this. I am sure others will chime in if I am off base on this. At any rate I personally would't run anything but Diesel fuel in my truck. Just my .02 Fran
What is the difference between all the grades, (the "+" meaning PRIST or equivilant)? I remember seeing a list of flashpoints for the different grades, JP4 being the the lowest. The Navy would not let our helos land on their ships with JP4 in the tank. Is jet fuel simply a mixture of diesel and kerosene, or is that an over simplification? What makes it dirty compared to the diesel at the T/A?
The jet fuels I am familiar with (JP-4 and JP-8) are kerosene based. So they'd be pretty similar to #1 diesel (although jet fuel has a bunch of additives). I wouldn't run it in a DuraMax, but I know guys that ran it in diesel cars in Germany...
The military does it for logistics. They only have to carry fuel, not ten kinds of fuel. There's even a company that converts Kawasaki KLX 650 motorcycles to run on diesel / jet fuel for the military. I have no experience myself but I've heard diesels don't run as well on jet. But they do run which works for Uncle Sam. I think there may be some tweaking they do to help them run on it.
I believe the problem for the Navy is/was that the JP4 fuel used by the Army & Air Force has a much lower flash point than JP5, making it extremely dangerous aboard ship. There is a slight density difference - I seem to recall JP4 was a bit lighter per gallon (talking a couple of tenths of a lbs per gallon). Back then (maybe now as well), Navy jet aircraft (planes & helos) could be run on either without much difference in performance/safety. However, if one of our birds took a mid-air drink off an Air Force tanker (drinking in JP-4), we had to leave it in the open air, on the flight deck (could not bring it into the hangar deck) until the aircraft's tanks check-out with an acceptable flash point. Usually took several flights/full tanks of JP-5 to get the JP-4 out of the system and the tanks sample flash points in limits.
The Army runs JP8. I believe it has less lubricity than #2. More like #1. Like Moto Head said it's for logistics reasons. I haven't seen any Dmaxs but plenty of 6.2 and 6.5's in HUMVEE's and CVCC's run it. It's hard to say long term how bad it is. The military is the wrong place to gauge civilian trucks by. Fuel quality can be uncertain at best especially outside of the US. Maintenance people are knowledgable but negelete doesn't begin to describe many of the drivers. Let's not forget the environment. It's amazing anything keeps running in the sand and dirt.
I'm sure some of the newer trucks with Cat's have higher pressure injection systems. The Freightliners have series 60 DDC's. A guy in my unit is fulltime maintenance at Ft. McCoy, WI. I'll ask him what kind of fuel related problem he sees the most.
In today's Navy we use two fuels,
F-76 aka DFM aka Diesel Fuel Marine, pretty much the same thing you buy at the pump.
JP-5 aka jet fuel, which is the same thing, just filtered more.
With JP-5 there is no allowable BS&W.
So if you're talking Navy jet fuel, yes it can be run in your truck and may perform better being that it starts out cleaner. Maybe JP-5 is the intended fuel for the OEM fuel filter...
I was practicing ship landings on a US Navy tanker off of Jacksonville, FL and asked the ship's captain what he was hauling. He replyed JP5 and Marine Diesel. I asked what's the difference. He answered, "When the jet fuel gets contaminated, it becomes Marine Diesel."
Ponz, it goes both ways, JP-5 starts out as regular diesel and is run though several filters and coalesors to take all the BS&W out of it. Just like you were told on the tanker, if JP-5 gets contaminated it's down graded to F-76.
My neighbor has a 1997 7.3 Powerstroke and a Volkswagen TDI. He is an aircraft mechanic and has been running "left over" (what was left in the jet after a trip) in both cars for 6 or 7 years. I wouldn't run it in my Duramax but he has 100k on the Ford and 150,000 on the TDI.
It's been awhile since I dug into this, but I'll see if I can remember some of the differences.
Generally speaking, as the JP number goes up, so does the flash point or the temperature at which the fuel will give off ignitable vapors. Interestingly enough, as the flash point goes up, the ignition temperature goes down. So the higher JP numbers not only have more heat energy per volume unit, but higher flash points and lower ignition temperatures.
If you consider the evironment in which jet aircraft operate, cold, you'll see why there are differences in the jet fuel and diesel fuel. IIRC, Jet-A and JP-4 are very similar, but JP-4 can be used at lower temperatures and used to be cut with up to 25% 80-87 octane AvGas for really cold temperatures.
JP-4 was developed a long time ago and for aircraft fuel systems that are not nearly as tightly spec'd as your Dmax. I used to run a flow bench for servicing turbine engine fuel nozzles, as well as working on light turbine aircraft, and their fuel systems don't run at any where near the pressures generated by the Bosch common rail system in the Dmax.
So, kerosene, Jet-A, JP-4 and diesel #1 are all quite similar but due to differences in how they are handled, at what point in the cracking or refining process they are pulled off, and what types of additives are put in along the way, I wouldn't recommend using something different that what is called for by your vehicle, be it ground transportation, sea born or aerial...
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