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Verified Technologies for SmartWay and Clean Diesel

Donaldson Technology—Series 6100 Diesel Oxidation Catalyst (DOC)

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

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Technology specifications

Series 6100 DOC. Baseline A. 

Engine Model/Application

Highway, heavy-heavy and medium-heavy duty, 4 cycle, non-EGR, model year 1991 - 2003; turbocharged or naturally aspirated 

Retrofit Fuel, Max Sulfur 15 parts per million (ppm)
Reduction in particulate matter (PM) 26%
Reduction in nitrogen oxide (NOx) n/a
Reduction in hydrocarbons (HC) 49%
Reduction in carbon monoxide (CO) 38%

Series 6100 DOC. Baseline B. 

Engine Model/Application
  • Highway;
  • Heavy-heavy and medium-heavy duty;
  • 4 cycle;
  • Non-EGR;
  • Model year 1991 - 2003;
  • Turbocharged or naturally aspirated
Retrofit Fuel, Max Sulfur 15 parts per million (ppm)
Reduction in particulate matter (PM) 20%
Reduction in nitrogen oxide (NOx) n/a
Reduction in hydrocarbons (HC) 66%
Reduction in carbon monoxide (CO) 41%


Baseline A - Baseline assumes an unmodified engine running on regular 2D (<500 ppm sulfur) fuel.

Baseline B - Baseline assumes an unmodified engine running on ultra-low sulfur diesel fuel (ULSD) (<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 15 ppm.
  2. The engine exhaust temperature must be at least 150° C during the duty cycle.
  3. The engine should be well maintained and not consume lubricating oil at a rate greater than that specified by the engine manufacturer.

No discernible fuel economy penalty is expected when used in a compatible application.

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Verification Letter from EPA

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