Emissions Technology - JOHN DEERE POWER SYSTEMS - #19

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Does the exhaust filter replace the muffler? Test results indicate that a muffler will not be required in most applications. Our experience has been that noise attenuation provided with the exhaust filter meets or exceeds that of a conventional muffler. However, each application is different, and actual results may vary. How will John Deere Interim Tier 4/Stage III B engines stand out from the competition? John Deere is an innovator in the commercial application of cooled EGR and variable geometry turbocharger (VGT) technologies for off-highway use. Throughout Tier 3/Stage III A, John Deere has gained experience with these technologies over a wide range of applications and has established a proven record of reliability; other engine manufacturers are just now considering adopting these technologies for off-highway applications. John Deere engines have a strong reputation of performance, durability and reliability, and we are designing our new engines to exceed those expectations. These new engines will also feature more power and increased performance, world-class fuel economy, reduced noise, and low overall operating costs. The SCR system has been adopted by several manufacturers. Why is John Deere choosing EGR first? For Interim Tier 4/Stage III B, John Deere is looking at not only fuel economy, but also total fluid economy. We have prioritized the needs of the owner and operator during every step of developing our complete Interim Tier 4/Stage III B lineup. The single-fluid approach of cooled EGR means the technology will be easy for operators to use and will not require additional fluid costs. John Deere has researched both of the different technologies, and from a global perspective, believes that cooled EGR with the addition of an exhaust filter is the best approach for meeting Interim Tier 4/Stage III B emissions regulations. John Deere remains confident that our world-class fuel economy position attained with Tier 3/Stage III A engines utilizing cooled EGR will be maintained with the use of only one fluid (diesel). Cooled EGR is a simple approach, has a proven track record throughout Tier 3, and is already supported by our global network of John Deere dealers. How does the total fluid consumption with an SCR system compare to conventional EGR diesel engine? The claim that engines designed to operate on selective catalytic reduction (SCR) consume less fuel is not accurate. Regarding engines utilizing SCR we must consider the total fluid consumption — that is, the consumption of diesel fuel and the diesel exhaust fluid (DEF) additive. Competitive engine manufacturers who utilize SCR have stated their engines could provide up to 5 percent better fuel economy compared to their non-SCR engines. When you consider that urea consumption is approximately 3 to 5 percent of diesel fuel consumption and the fact that urea cost is similar or higher than diesel fuel, there is no advantage for engines utilizing SCR from a total fluid consumption and cost perspective. Depending on the engine model, John Deere Interim Tier 4/Stage III B bare engine fuel consumption will be similar or equal to Tier 3/Stage III A. Overall fuel economy will improve in some vehicles/applications due to drivetrain optimization and engine/vehicle integration. John Deere Tier 3/Stage III A engines currently hold a 5 to 10 percent fuel economy advantage when compared to most competitive engines. As a result, John Deere Interim Tier 4/Stage III B engines will continue to maintain their fuel-economy leadership without utilizing SCR for Interim Tier 4. In regards to decreased system cost, research shows that Interim Tier 4/Stage III B engines with SCR systems are comparable in total installed engine cost compared to engines utilizing cooled EGR and exhaust filters. When considering SCR system cost, end users will need to consider sourcing, inventory and distribution costs associated with SCR. John Deere engines/vehicles will continue to provide the best value with a simple (one fluid) and proven technology (cooled EGR and variable geometry turbochargers). 19