bhagu

Hi,

This is the response from Shell regarding the diesel cetane rating I enquired about -

Thank you for taking the time to share your concerns.

Shell Diesel fuel meets the minimum ASTM D975 specification for cetane index which is 40. The actual/exact Cetane index may not be constant throughout the year and we cannot tell the exact rating of any particular area. However we can give ballpark/average figure for Cetane Index which is between 44-50 in USA for ULSD.
If you have additional questions, please contact Shell Customer Care toll-free at 1-888-GO-SHELL (1-888-467-4355).

uberwgn

No surprises there.

The only places I'm aware of in the USA that have something closer to 48 cetane are CA and TX. Yes, S15 (ULSD) is supposed to be a superior quality fuel compared to the S500 fuel.

Keep in mind, the cetane value is not indicative of quality. People think it's "equivalent" to the AKI of gasoline....it's not.

You worry about cetane value when you are having cold weather starting problems. Think Canada.

I'd be far more concerned about water content, lack of lubricity, etc.

bhagu

So how do we improve the lubricity and water content if the fuel is lacking that?

bhagu

More from Shell - upto 5% biodiesel!

When it comes to Shell Diesel: In the US, Shell offers ULSD (Ultra Low Sulfur Diesel) which may contain up to 5% biodiesel (again, designated as "B5"). However note that each Shell station is independently owned and may elect to offer a different NON-SHELL biodiesel blend at their discretion. The diesel fuel dispenser is required to be properly labeled as to whether it is a Shell branded product, and must show the bio content of the diesel being dispensed. So please look for this labeling and if you should have any questions, please discuss directly with the specific Shell station OWNER (not necessarily the Attendant, who may not know).

In addition, all Shell-Branded Diesel meets the ASTM D 975 Specification. Again, all Shell branded diesel is blended to contain a max of 5% bio content (ie max B5) across the USA. If the retail dispenser is labeled 6%-20% biodiesel, then it is not a Shell-branded fuel. And if it is a diesel fuel with more than 5% biodiesel content, then the dispenser must also have a label that states that it is not a Shell-branded product.

For more information concerning Shell Diesel Fuel, please visit the following internet link: http://www.shell.us/products-service...ls/diesel.html

Bürgermeister

... and then there is Minnesota, where they mandate, yes, mandate B10 biodiesel during the months of April through September.

idale

For lubricity (and for cetane) you can use an additive if necessary, but for water content (the issue is water contaminating the diesel due to poor seal on the tanks) your only option is to find a better station.

Ouch, that sucks. I'm pretty sure that VAG requires only up to B5, but by selling in the state then surely that's some sort of implicit acceptance of B10 if it's a state requirement.... Hopefully they keep an eye on the fuel filters since there's more of a chance of getting clogs with higher biodiesel content (I don't know if it's a likely problem with B10 vs. B5, though, just that the more bio in the blend the higher the chance is).

bhagu

This is the reply I got from sunset audi in oregon. I had bought my winter package (I got nice discounted deal on 17" rims (used)).
++++++++++++++++++++++++
I understand you spoke with Jeff about the diesel fuel additives on the phone. He has brought to my attention that the newer clean diesel TDI’s should not use any additives. The additive may help your pump but burn up the particulate filter system. It is not recommended by Audi to use any fuel additive with your Q5. Please let us know if you have any other questions

Hockeymonkey

I was just at the Shell station in Portland and it stated that the diesel contains 10% ethanol. Is the 10% ethanol "biodiesel"? Why would they call that out on the gas pump?

Bürgermeister

This bulletin from MB makes for an interesting read: http://mercedes-benz.custhelp.com/ci...0Biodiesel.pdf

centurion70

Ethanol is used in certain blends of gasoline (petrol), and it is different from biodiesel. I suspect the label you saw was either a mistake or intended to cover a nearby ethanol/gasoline pump.

Labels like this are typically governed or required by state law. In some states, including Oregon I believe, there are tax incentives to selling ethanol gasoline blends and biodiesel blends.

My understanding is that true Shell diesel contains no more than 5% biodiesel, which is consistent with Audi's warranty and recommendations. However, the owner of a given Shell station can choose to sell a non-Shell diesel blend, in which case it may contain more than 5% biodiesel. The pump should be labeled to indicate clearly whether the diesel is from Shell or some other supplier.