Walking the show floor at the National Truck Equipment Association Work Truck Show in March, there was much talk in the OEM booths on how drivers will be opening that little blue cap on their diesel trucks and filling a tank with diesel exhaust fluid (DEF) made from urea. The urea fill is inherent in one of the technologies (SCR, or selective catalytic reduction) used to meet the 2010 diesel emissions standards. (The other is EGR, or exhaust gas recirculation, which does not require a DEF fill.)

The bottom line for fleets is there is now a premium of at least $6,000 on new emissions controls for diesel trucks, as well as new servicing requirements moving forward. And the new diesel regulations have shifted product offerings in the truck market. 

What's New and No Longer

Freightliner Custom Chassis is offering a gas-engine option (GM's 6-Liter V-8) for the first time in its new, redesigned step van. Conversely, parent company Daimler has discontinued its gas engine option on the (now rebadged) Mercedes Sprinter.

Nissan introduced its first commercial production vehicle for North America, Nissan NV. The high-roof van will directly compete with the Sprinter, though no diesel engine is offered.

Ford has built its own Power Stroke diesel engine after severing ties with Navistar. The new Power Stroke is "all that." However, while the Super Duty gets the new diesel, there is no longer a diesel option on E-Series vans.

Remember the talk a couple of years ago regarding a diesel option in half-ton pickups? GM and Ford have shelved that idea for now. Chrysler is talking with Cummins regarding a light-duty diesel engine for Ram, though plans are not definitive.

Alt-powered vehicles are finally migrating from test fleets to fleet sales. Roush has engineered a superb propane conversion for Ford's F-150, F-250 and F-350 pickups. Freightliner Custom Chassis is offering an all-electric step van in Q1 2011. Smith Electric will announce three new markets soon for its all-electric cube van. The electric market is growing, though beyond "first adopters," the price point is still prohibitive for many.

New Servicing Requirements

Get used to filling that urea tank. Generally, DEF is consumed at a rate of 2 percent of diesel fuel consumption. Frequency of fill-ups will vary according to the size of your DEF tank, which varies by manufacturer. However, there does not seem to be scientific consensus yet as to how many miles you'll get to the size of your tank.

For instance, Isuzu says DEF in its 7.4-gallon tank will evaporate after 3,000 miles, while Daimler claims the 7.4-gallon tank in the Sprinter will last until 10,000 miles. One manufacturer's rep admitted, "We still just don't know at this point."

By law, new diesel trucks are required to have an escalating warning system to alert the driver when the urea tank is approaching empty. Manufacturers have slightly different coping mechanisms should the driver actually let the tank run dry.

Some allow a certain number of vehicle starts before the vehicle won't run at all. Others will run in "limp mode." That means your truck will start, but won't go faster than 4 mph. At that point it's probably easier to have the DEF delivered to you.

With all the built-in warnings, you have to be pretty stupid to let the tank run dry. One imagines the idiot factor will come into play on the consumer side much more than with fleet drivers.

Retail per-gallon costs for DEF can run below $2 in bulk supplies and higher than $4 in small bottles. In Europe, DEF costs the equivalent of $2.50 per gallon. The trade-off is a fuel economy boost of 5 to 10 percent over previous diesel engines.

A Diesel Migration?

Diesel model selection may have protracted slightly when looking at a single OEM's portfolio, but diesel power certainly isn't going to lose much market share on the medium- and heavy-duty work truck front either. Manufacturers continue to invest heavily in diesel technology and keep upping the ante in performance and capabilities.

Whether diesel sales migrate slightly to other powertrains is less relevant than the fact that there is now a greater array of powertrains - electric, hybrid, propane, natural gas, gas and diesel - to choose from to do the job.

For fleets, vive le competition, vive le choice.