Why it’s still not that easy to find diesel fuel

The age of diesel seems to be coming back. Lately, we’ve driven a lot of great diesel cars, SUVs, and trucks, from the top-scoring Mercedes-Benz E250 Bluetec to the ½-ton Ram 1500 pickup. Likewise, the U.S. Census Bureau reports that the percentage of gas stations selling diesel went up from about 35 percent in 1997 to more than half in 2007. Yet our experience shows it hasn’t really gotten any easier to find a place to fill up. It may actually be harder.

More than once this year, we’ve found ourselves looking for a diesel station with the needle pegging Empty, only to pull up to a pump and find we can’t use it.

The problem is that there’s no longer one type of fuel that can fill up any diesel-powered vehicle; there are five different types, including ones for off-road equipment (bulldozers and such), heavy trucks, and cars. And even within the on-road diesel fuel, there are two types of nozzles, large ones for trucks and smaller ones for cars.

And that’s where we’ve run into problems, trying to fill up at stations with car pumps at islands designed for passenger cars. Once, driving our excellent Mercedes-Benz E250 Bluetec, we showed up at a station that had only one available diesel pump, only to find that it was equipped with a large truck nozzle that wouldn’t fit in the sedan’s filler neck. Another time, on a long trip to Boston in our BMW 328d, I was counting on filling up close to my destination, where I know fuel prices are lower. I was pleased to find a diesel pump at a little-used rest area right outside the city where we commonly stop, then dismayed to find the diesel pump tagged with an “out-of-order” sign. The only other diesel pump available where the attendant tried to send me was at the truck island, where I naturally found another large nozzle that wouldn’t fit our BMW.

For tips on saving gas—or diesel—visit our guide to fuel economy.