ACERT™ Technology

Cat machines are rolling off assembly lines with the latest in engine technology. The first model

to ship was the D8T. Several other models followed suit including the D9T, 365, 385, and four

Articulated Trucks. As of the end of April, a total of 26 machine models are available! Each of

these machines use Caterpillar engines with ACERT™ Technology, the result of more than $500

million in research and development and more than 250 patents. The engines are compliant with

the United States EPA Tier 3 emissions regulations governing off-road machines, which took

effect January 1, 2005 for engines of 300 to 750 horsepower.

ACERT Technology is another example of why Caterpillar continues to be the North American

leader in on-highway engines. Truck engines with ACERT Technology log more than 70 million

miles each day. In fact, Caterpillar factories ship more than 16,000 of those engines each month.

That on-highway record, coupled with Caterpillar's decades of experience in the off-road

business, means customers will continue to receive the ultimate in engine performance and

machine production.

Emissions regulations for machine engines are not new. The first went into effect in 1996, and

Tier 2 regulations were applied in 2001. Those standards were met by adapting existing

technologies, but the aggressive Tier 3 requirements dictated breakthroughs.

Caterpillar introduced ACERT Technology to meet EPA '04 regulations for on-highway trucks.

Earlier, Caterpillar machine engines with ACERT Technology began field-testing across the

United States, Canada and Europe. Now there are more than 350 such machines in the field.

Combined, they have worked over 520,000 hours. These machines are working in the multitude

of applications typical for Cat equipment—from construction to mines to landfills. And they are

working in a wide variety of conditions. One track-type tractor has performed successfully in a

road-building project at 8,100 feet altitude.

ACERT Technology represents a series of evolutionary and incremental improvements

developed by Caterpillar. For example:

The fuel system allows for multiple injections each combustion cycle. Small amounts of

fuel are injected at precise times to achieve the combined goals of fuel economy and

lower emissions.

An advanced air system provides more cool air in the combustion chamber. A wastegate

turbocharger provides excellent low-end response. In addition, crossflow cylinder heads

provide a direct path of air to the engine.

Caterpillar engineers worked with approximately 125 variables to find the optimum balance.

There are more than 10 million possible combustion combinations. Those engineers were

challenged by the highly intertwined relationship of (1) reduced emissions, (2) engine

performance, (3) fuel efficiency and (4) engine durability. Those are not necessarily

complimentary objectives. Improving emissions, for example, can have an adverse effect on fuel

efficiency. Their overriding goal is no different than the goal Caterpillar has had since its

inception—to provide customers with the lowest owning and operating costs, and the lowest cost

per unit of material moved.