Ultra Low Sulfur Diesel

I purchased my 2007 ML 320 CDI in March 2007. The manufacturer requests that only ultra low sulfur diesel fuel be used. Ultra low sulfur is more common now but when I purchased the ML it was difficult to find the correct fuel. I always starting looking for a station when the fuel guage was at the 1/4 mark. Well, I knew it was only a matter of time before I was unable to locate a fuel stop. With the low fuel light on I pushed the mileage to 35 miles before I found ultra low sulfur diesel.