What's the label on all the diesel pumps mean?

[MDM]

What does the label I see on diesel pumps mean that says something like "not for use in 2007 model vehicles or later"? Does this mean 2007 and under? What does it mean?

 

[browns40]

Hi MDM,

2007 marked the big transition from the low sulphur diesel (LSD <500ppm) to the Ultra-Low Sulphur Diesel (ULSD<15ppm) to be used in on-road vehicles...

Emissions systems changed, catalysts were modified, and engine components were changed to accept this dryer fuel in the 2007-2008 period...

Sounds like you are finding low-sulphur instead of ULSD somewhere, which sounds really odd, as every label I see around Maine is toting the ULSD "approved for 2007 & later vehicles), but???

New emissions systems are--I guess--not made to handle the old stuff, and warn of major problems running the old fuel through them...

Anyone familiar with the exact mechanisms changed in the engines themselves & exactly what the heck the "dirty old fuel" does to these new systems?

 

[Z-Michigan]

You are right on the sulfur. In general, 2007+ MY diesels need diesel particulate filters to catch the soot, which then gets burned into gases during regeneration cycles. Thing of the DPF's as like catalytic converters on cars, though they do a different thing and do it in a somewhat different way. Well, sulfur destroys the DPF material and makes it ineffective, requiring replacement. Put LSD (500pm) in a vehicle with a DPF and after a moderate amount of use it's destroyed. The 15ppm ULSD requirement was implemented to allow use of these DPF's.

LSD has been outdated for road use since October 2006. I was not surprised to see it a couple months after that, but seeing it now is a bit surprising. Is it at offroad-only diesel pumps?

2007+ MY diesels also have low limits on NOx emissions, but to my knowledge those are usually managed with EGR systems.