The Cat® C4.4 engine meets U.S. EPA Tier 4 Final, EU Stage V, Japan 2014, and Korea Tier 5 emission standards.
The D4 emits up to 5% less CO2 than the previous D6K2*.
Cat diesel engines are required to use ULSD (ultra-low sulfur diesel fuel with 15 ppm of sulfur or less) or ULSD blended with the following lower-carbon intensity fuels up to: 20% biodiesel FAME (fatty acid methyl ester) ** or 100% renewable diesel, HVO (hydrogenated vegetable oil) and GTL (gas-to-liquid) fuels. Refer to guidelines for successful application. Please consult your Cat dealer or “Caterpillar Machine Fluids Recommendations” (SEBU6250) for details.
Auto Engine Speed Control helps reduce unnecessary fuel burn and greenhouse gas emissions by allowing the engine to automatically go into idle mode when the machine is not working.
AutoCarry™ automates blade lift to reduce track slip for maximum efficiency on each pass to help lower fuel burn and greenhouse gas emissions.
Cat® Grade with Slope Assist™ helps you avoid costly rework and wasteful fuel burn and greenhouse gas emissions by automating your blade position without a GPS signal.
Cat® Grade with 3D automates blade movements using a GPS signal helping you follow a grade design, reducing fuel burn and greenhouse gas emissions by improving efficiency and accuracy.
Extended maintenance intervals not only reduce downtime but decrease the amount of fluid and filters that are replaced over the life of the machine.
VisionLink® displays the CO2 emissions for monitored assets, calculated by fuel type for the Runtime Fuel Burned each day in a selected date range.
Remote Flash minimizes downtime and maintenance time while keeping your asset running with maximum efficiency. Alerts for machine updates are sent virtually from your Cat dealer and updates can be deployed without a dealer technician needing to be onsite.
Remote Troubleshoot decreases maintenance time and keeps your machine running with maximum efficiency by allowing your Cat dealer to virtually test the machine while working. Once a problem is identified, a technician can fix it the first time, saving time and money.

*All comparisons to D6K2. Productivity, fuel and CO2 emissions vary by application. CO2 emissions calculations based on a reference work cycle using 2.2 U.S. gallons per hour of #2 U.S. diesel fuel based. Applies IPCC2006 methodology using U.S. EPA Emissions Hub emission factors. Includes DEF (diesel exhaust fluid) related CO2. Fuel measurements are at 15°C. Estimated average fuel consumption improvements are based on tests or Product Link® data where available. Productivity improvements are based on test data.
**Engines with no aftertreatment devices can use higher blends, up to 100% biodiesel.