N MAY 2004, THE ENVIRONMENTAL Protection Agency (EPA) issued its anticipated final rule regarding non-road diesel engines. Similar to the current regulations for on-road diesel engines, the non-road diesel engines rule will reduce emissions by reducing the sulfur content in diesel fuel and by requiring new emissions-control technology by 2008.

According to the EPA, the new rule will reduce non-road emissions by more than 90 percent by 2030 by reducing emissions of nitrogen oxides by 738,000 tons annually and particulate matter by 129,000 tons. The final rule, which was first proposed in April 2003, will apply to heavy-duty industrial engines, such as bulldozers and tractors. EPA's rule will likely lead to the reformulation of diesel engine oils.

The final rule corresponds to existing EPA diesel emission reduction programs for highway trucks and buses by requiring a phased-in reduction in sulfur levels in the diesel fuel used by non-road engines by 2010 and requiring new technology to be installed in those engines by 2008. Specifically, the rule requires 99 percent of the sulfur currently found in diesel fuel to be removed. By 2007, the maximum sulfur level allowed will be 500 parts per million (down from the current "uncontrollable level" of 3,000 parts per million). By 2010, that level will have to be further reduced to 15 parts per million.

The NOACK Volatility Test determines the evaporation loss of lubricants in high temperature service. Teh more motor oils vporize, the thicker and heavier they become, contributing to poor circulation, reduced fuel economy and increased oil consumption, wear and emissions. A maximum of 15 percent evaporation loss is allowable to meet API SL and ILSAC GF-3 specifications. As shown in the graph, AMSOIL 15W-40 Synthetic Heavy Duty Diesel and Marine Motor Oil outperformed its nearest competitor by more than 30 percent.

The extremely low volatility of AMSOIL 15W-40 Synthetic Heavy Duty Diesel and Marine Motor Oil allows it to maintain its superior protective and performance qualities throughout extended frain intervals, even when faced with severe operating temperatures. In addition, oil consumption and emissions are minimized and fuel efficiency is maximized.