Question about Diesel fuel

On a recent trip across country with a 2006 diesel F-350, I noticed these little signs on the diesel pumps at just about every gas station we stopped at. The signs said something to the effect of

This leads to two questions:

  1. Why would this fuel hurt MY2007 engines? Did they change something fundamental in the design of these engines?

  2. Being that MY2007 diesel vehicles are on the road, what the heck are they supposed to use for fuel? These stickers were at every station I can remember stopping at.

So, dopers, anybody know what’s going on here?

Mines Mystique

Sulfur and emissions standards.

“Regular” low-sulfur diesel fuel has 500 ppm of sulfur. The new engines are designed to be run on what’s called ULSD (ultra-low sulfur diesel) fuel that has a max of 15 ppm sulfur.

Much like how running leaded gas in a car meant for unleaded will damage the catalytic converter, running the higher sulfur fuel in a ULSD engine will damage components and will likely void your warranty. It’s also illegal, so you could be hit with some stiff civil penalties.

The gas stations with those warning stickers simply haven’t switched over to the new fuel. They’re running out of time - the federal cutoff date to stop selling 500 ppm fuel if the gas station chooses to* is October 15. In California, the deadline was June 1.

  • Retailers are currently free to not sell ULSD at all. Most will, since they’ll otherwise alienate everyone that has a 2007 truck. Any retailers that don’t choose to sell the stuff will have until 2010 to switch.

For the “green” folks - they’re in luck as B100 (100% biodiesel) is already beating the 15ppm requirement. Some care needs to be taken if they run B20 (20% biodiesel, 80% regular) that they’re blending it with USLD.

Ooh, ooh, we were just covering this at work yesterday, although I am not an expert by any means. Mercedes-Benz has the E320 CDI (diesel) which came out a few years ago. For 2007 they have released most of our models, but not the new diesel. Also, we have the ML320CDI, R320CDI, and GL320CDI coming out. They are all built and are stuck at either the factories or customs waiting for the new low-sulfur diesel to come out.

The new 2007’s will not run on the current diesel, but just in case they are released early the gas stations have warnings on their pumps this so the new cars are not ruined by this low-sulfur diesel. However, the older diesels will continue to run using either the higher or lower sulfur grade diesel.

It’s all about the environment.

Or… what** gotpasswords** said.

I remember a few years back that older diesel engines could not run on the new ultra low sulfur fuel. Did the older fuel have sulfur added as some kind of lubricant for the injectors and pump?

I don’t quite understand. I think this means that retailers don’t have to sell the new stuff yet, but they’ll soon be prohibited from selling the old stuff. And in 2010 they’ll be required to sell the new stuff. Is that right?

Yup. Outside of California, retailers are free to not sell ULSD for the next four years. They must prominently disclose that they’re not selling it, though.

But, as FormerMarineGuy said, there’s boatloads of new vehicles that are essentially unsaleable until the retailers start selling USLD. Given the market pressures from the automakers wanting to sell new vehicles, and the public wanting to buy new vehicles, I can’t imagine there will be too many gas stations that will willingly wait until 2010 to start selling USLD.

Every gas station I go to has three grades of gas; regular (87 octane), plus (89-91) and premium(91-93). Three nozzles on one pump, two to ten pumps per station.

How hard could it be to make a pump with a nozzle for “regular” diesel, and a nozzle for the USLD?


It’d be illegal. If they sell any USLD, they have to sell only USLD from here on out.

You pretty much have it.
Actually, there are additives under way to allow older diesels to run on the new stuff without excess wear.
These guys:
have one under development. You’ll notice they have an FP60 “Fuel Power 60” product.
There’s an FP3000 product that will go into production once ULSD fuels become an issue for commercial diesel engine owners. The chemistry has already undergone testing at Southwest Research Institute ( that isn’t published.

Actually, the product is all ready. They discovered that the only way they can get one of the ingredients is by buying a swimming pool worth of it, so they need one big fleet sale or other order before they can begin commercial production.