I thought i would post this to help some people understand why our trucks get the mileage that they get, and some interesting facts on the diesel fuel in this country vs the rest of the world.

This motor the 6.7 along with the previous 6.0 were designed and tested using European grade diesel fuel which has a minimum of a 51 centane rating vs the U.S of 40 to 45 .
Basically its like running a sports car thats required to run on 93 octane but putting 87 octane in it.
Sure it will run ,but it will run like crap and get terrible mileage .

I know since the day i drove my truck off the lot every tank i run half a bottle of the gray power service cetane boost which increases the number 6 points and in the winter time i mix half of the white power service with the gray to prevent gelling and remove water . I notice a huge differance if i don't add either one to a tank full , there is a very noticable performance decrease without adding a centane boost ,plus the truck goes though less regens when combined with a centane boost product.

From www.wikipedia.org, article found HERE.

Cetane number or CN is a measurement of the combustion quality of diesel fuel during compression ignition. It is a significant expression of diesel fuel quality among a number of other measurements that determine overall diesel fuel quality.
<table id="toc" class="toc"> <tbody><tr> <td> Contents

[hide]

• 1 Definition
• 2 Typical values
• 3 Chemical relevance
• 4 Measuring cetane number
  • 4.1 Ignition quality tester
  • 4.2 Cetane index
  • 4.3 Industry standards
• 5 Further reading
• 6 See also
• 7 References
• 8 External links

</td> </tr> </tbody></table> [edit] Definition

Cetane number or CN is actually a measure of a fuel's ignition delay; the time period between the start of injection and start of combustion (ignition) of the fuel. In a particular diesel engine, higher cetane fuels will have shorter ignition delay periods than lower cetane fuels. Cetane numbers are only used for the relatively light distillate diesel oils. For heavy (residual) fuel oil two other scales are used CCAI and CII.
[edit] Typical values

Generally, diesel engines run well with a CN from 40 to 55. Fuels with higher cetane number which have shorter ignition delays provide more time for the fuel combustion process to be completed. Hence, higher speed diesels operate more effectively with higher cetane number fuels. There is no performance or emission advantage when the CN is raised past approximately 55; after this point, the fuel's performance hits a plateau.
In Europe, diesel cetane numbers were set at a minimum of 38 in 1994 and 40 in 2000. The current standard for diesel sold in European Union, Iceland, Norway and Switzerland is set in EN 590, with a minimum cetane index of 46 and a minimum cetane number of 51. Premium diesel fuel can have a cetane number as high as 60.<sup id="cite_ref-0" class="reference">[1]</sup>
In North America, most states adopt ASTM D975 as their diesel fuel standard and the minimum cetane number is set at 40, with typical values in the 42-45 range. Premium diesels may or may not have higher cetane, depending on the supplier. Premium diesel often use additives to improve CN and lubricity, detergents to clean the fuel injectors and minimize carbon deposits, water dispersants, and other additives depending on geographical and seasonal needs.
Dimethyl ether may prove advantageous as a future diesel fuel as it has a high cetane rating (55) and can be produced as a biofuel.<sup id="cite_ref-1" class="reference">[2]</sup>
Alkyl nitrates (principally 2-ethyl hexyl nitrate [1]

) and di-tert-butyl peroxide are used as additives to raise the cetane number. Biodiesel from vegetable oil sources have been recorded as having a cetane number range of 46 to 52, and animal-fat based biodiesels cetane numbers range from 56 to 60.<sup id="cite_ref-2" class="reference">[3]</sup>
[edit] Chemical relevance

Cetane is an un-branched open chain alkane molecule that ignites very easily under compression, so it was assigned a cetane number of 100, while alpha-methyl napthalene was assigned a cetane number of 0. All other hydrocarbons in diesel fuel are indexed to cetane as to how well they ignite under compression. The cetane number therefore measures how quickly the fuel starts to burn (auto-ignites) under diesel engine conditions. Since there are hundreds of components in diesel fuel, with each having a different cetane quality, the overall cetane number of the diesel is the average cetane quality of all the components.
[edit] Measuring cetane number

To measure the cetane number properly is rather difficult, as it requires burning the fuel in a special, hard-to-find, diesel engine called a Cooperative Fuel Research (CFR) engine, under standard test conditions. The operator of the CFR engine uses a hand-wheel to increase the compression ratio (and therefore the peak pressure within the cylinder) of the engine until the time between fuel injection and ignition is 2.407ms. The resulting cetane number is then calculated by determining which mixture of cetane (hexadecane) and isocetane (2,2,4,4,6,8,8-heptamethylnonane) will result in the same ignition delay.
[edit] Ignition quality tester

Another reliable and more precise method of measuring the cetane number of diesel fuel is the Ignition Quality Tester (IQT^TM). This instrument applies a simpler, more robust approach to CN measurement than the CFR. Fuel is injected into a constant volume combustion chamber in which the ambient temperature is approximately 575°C. The fuel combusts, and the high rate of pressure change within the chamber defines the start of combustion. The ignition delay of the fuel can then be calculated as the time difference between the start of fuel injection and the start of combustion. The fuel's derived cetane number can then be calculated using an empirical inverse relationship to ignition delay.
[edit] Cetane index

Another method that fuel-users control quality is by using the Cetane index (CI), which is a calculated number based on the density and distillation range of the fuel. There are various versions of this, depending on whether you use metric or Imperial units, and how many distillation points are used. These days most oil companies use the '4-point method', ASTM D4737, based on density, 10% 50% and 90% recovery temperatures. The '2-point method' is defined in ASTM D976, and uses just density and the 50% recovery temperature. This 2-point method tends to over-estimate cetane index and is not recommended. Cetane index calculations can not account for cetane improver additives and therefore do not measure total cetane number for additized diesel fuels. Diesel engine operation is primarily related to the actual cetane number and the cetane index is simply an estimation of the base (unadditized) cetane number.
[edit] Industry standards

The industry standards for measuring cetane number are ASTM D-613 (ISO 5165) for the CFR engine and D-6890 for the IQT.
[edit] Further reading

• <cite>Internal Combustion Engine Fundamentals</cite>, John B. Heywood, McGraw Hill, 1988 ISBN 0-07-100499-8
• <cite>Automotive Fuels Reference Book</cite>, Keith Owen, Trevor Coley SAE, 1995, ISBN 1-56091-589-7

 

"This motor the 6.7 along with the previous 6.0 were designed and tested using European grade diesel fuel which has a minimum of a 51 centane rating vs the U.S of 40 to 45"

That makes no sense. Why would Ford or any other engine manufacturer design and test an engine for use in the USA with fuel not available in the USA. Where did you get this information? I would like a link to a reputable site!

Programming is designed and sensors are calibrated for the fuel available for the "everyman" middle of the road fuel, altitude, road conditions/types and weight of loads.

 

it was from a wikipedia site. I posted this to help inform people that U.S grade diesel is not comparable to what other countries get for fuel.

Ford did design this motor the 6.7 to work with U.S grade diesel and bio diesel, just research there new diesel engine building facility in Germany in a town east of london. They are making smaller displacement diesel motors that the U.S will never see , because of our EPA requirements on fuel and motors.

I really didn't wan't to get in a huge discussion over this , just trying to help some why we get bad mileage with our fuel .

If my memory serves correct,i saw posted in a discussion on a fuel site that
Shell is around 45 -47 summer , winter blend is 42-44
Bp is right around the same

The rest like Marathon ,Pilot , Petro were around 43- 45 summer,and winter was 40 -43

 

I appreciate the info. I've seen that we should be using a cetane booster in every tank. I even read in the maintenance tips pdf that someone posted yesterday that Ford actually recommends it as well. "Diesel fuel quality is critical for reliable engine operation. Motorcraft Cetane Booster & Performance Improver, PM-22-A (US) / PM-22-B (Canada) can be added to improve fuel economy, starting ability, and reduce engine wear." I haven't added this to my truck, but I'm going to run out today and get a case and start using it every tank.

 

i work for BP and have been on the refining side and now do the additives and if you buy the BP branded fuel and is says bp premium diesel it is 50 octane we mandate all bp branded stations to carry 50 octane diesel! so you know where i fill my truck up at! but i know shell is close 47 or closer!

 

I know my seat of the pants impression is that my truck runs better when I use a cetane improving additive, but are there any dyno tests that show either a power or mpg benefit?

 

I have also read that BP carries 50+ (51 is actually what I have seen). Small point, though: it's cetane, not octane. They are two very different measurements.

 

Great information...Thanks for posting...Reps given

 

I don't want to hijack the thread, but...

Also I could be wrong, but think it would have to be sold as BP "Premium Diesel". If it (or Shell's for that matter) is not labeled as such you are just as likely to get Valero, Motiva (Shell), Chevron, Alon, Marathon, Delek, etc ULSD.

The same distribution systems (pipelines, etc) are used to carry all refiners products. Most of those products, I.E. 87 octane gasoline, end up in the same tanks at terminals near where the product will be sold to end customer.

The additives/detergents are added at the terminal when the product is loaded into the delivery truck, so if it is going to a Chevron station the Techron is added at this point even though the "base 87 octane gasoline" could be from any of the refiners.

I suspect that the Cetane additive is added at the terminal and makes it "BP Premium Diesel".

I learned a very informative lesson last week about why diesel costs more than gasoline, but I won't hijack the thread any further.

 

I had a good friend who worked for the Pipelines and from what I remember him telling me, They do try and seperate out the various batches of fuel that pass thru the pipeline. so yes they do use a common pipeline, But each batch of fuel has a seperator placed into the pipe between loads to keep them seperate. i.e . Chevron my pump 6000 gallons of regular, then Phillips may pump 8000 of Premium, back to Chevron pumping 4000 gallons of Mid premium and so forth.

The plug is a liquid that doesn't mix with the fuel when under pressure, The receiving pump station then pulls out the stated number of gallons and places them in a tank for the owner. The plug is removed and the next batch of fuel is pulled and placed in a storage tank for the respective owner.


Now do I believe there is some intermixing of fuel between refineries, absolutely. But in general, If you buy Chevron, you are getting fuel that was refined by Chevron and so forth. If you buy unbranded fuel from the corner C-Store. I'm sure they buy from a regular wholesale account an their fuel may come from any number of distributors, probably from a spot market of who offered the best price for the delivery or the month.

 

i am very embarrassed that i put octane! i wasnt thinking straight or something!thank for pointing that out!! being in the oil/refining industry for 31 years now im quite embarrassed! my appologies

 

What would be great, is if you could do a "before" and "after" mpg comparison, that would be interesting to know !

 

As someone that sailed (worked) on Oil Tankers as a Chief Engineer for over 20 years, I can say that you will never know where your duel was refined. We were on contract to Chevron USA for a long time and yes we did load a different companies refineries. Also sometimes we would pick up a Full Load 230,000 bbls. (9,660,000 Million Gallons) and would than travel to several different oil companies terminals and pump of what ever was needed.

The difference in comes at the terminals where they add whatever additives before it hits the trucks but the base product is the same.

 

I don't think the question is about where the fuel is refined. Also, I know that the fuel a company sells comes from many different sources. Some is, in fact, refined at their own refineries. Some is bought. Supply, demand, etc. etc. etc. The question is about what we put in our tanks. Each company has its own regulation for what will be sold to the public under their banner. Chevron and BP are known to have the highest standards.

 

Will do. I write down every fill up (miles, trip miles, gallons, mpg, cost) so I have the first 8800 or so miles as the baseline. I just added the first bottle to my last fill up a few days ago, so I'll watch it and reply if I see any mpg improvement in the next few tanks. That would be nice, as I'm averaging under 13mpg through the first 8800 miles (no towing, mostly city).