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Verified Technologies for SmartWay and Clean Diesel

Caterpillar Technology—Diesel Particulate Filter (DPF)

This retrofit technology is included on EPA's Verified Technologies List for Clean Diesel.

On this page:

Technology specifications

Engine Model/Application

Nonroad, 4-cycle, non-EGR equipped, model year 1996-2005, turbocharged engines with power ratings 130 ≤ KiloWatts < 225 (174.2 ≤ Horsepower < 301.5)

Retrofit Fuel, Max Sulfur 30 parts per million (ppm)
Reduction in particulate matter (PM) 89%
Reduction in nitrogen oxide (NOx) n/a
Reduction in hydrocarbons (HC) 93%
Reduction in carbon monoxide (CO) 90%

a Baseline assumes an unmodified engine running on 15 ppm sulfur fuel.

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Criteria to achieve emission reductions

The following operating criteria must be met in order for appropriately retrofitted engines to achieve the above emissions reductions:

  1. The engine must be operated with a fuel that contains a sulfur content of no more than 30 ppm.
  2. The DPF requires an exhaust temperature of 260° C for 40% of the cycle for NOx:PM ratios of less than or equal to 20:1 and for NOx:PM ratios equal to or greater than 25:1, only 200° C for 40% of the cycle is required. (As there may be significant variations from application to application, Caterpillar will review actual vehicle operating conditions and perform temperature data-logging prior to retrofitting a vehicle with their PM filter system to ensure compatibility.)
  3. Caterpillar will install a backpressure monitor and high pressure indicator light on all vehicles equipped with this DPF.
  4. The engine should be well maintained and not consume lubricating oil at a rate greater than that specified by the engine manufacturer. Crankcase oil burning systems may not be used with this product.
Caterpillar has indicated there is a negligible (approximately 1 percent) fuel economy penalty with the use of this technology.

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Verification Letter from EPA

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