Tier IV engines are designed to lower the number of particulates and nitrogen oxides that are emitted into the atmosphere from heavy equipment and other machines. They were developed so that large engines can meet strict EPA emissions regulations, while also delivering improved fuel efficiency and better performance than previous machines.
The different types of Tier IV engines
There are two primary categories of Tier IV compliant engines, Cooled Exhaust Gas Recirculation (CEGR) and Selective Catalytic Reduction (SCR).
CEGR – This system implements an exhaust gas recirculation cooler (EGR) to reduce the combustion temperature of the engine by mixing fresh air with exhaust gas. Particulates are then trapped by a diesel particulate filter (DPF) to prevent them from being emitted into the air. The remaining emissions are harmless N2 and CO2 gases.
SCR – Selective Catalytic Reduction is a process that inserts a liquid reductant agent known as diesel exhaust fluid (DEF) through a special catalyst into the exhaust stream of the engine. The result is a chemical reaction that converts nitrogen oxide into nitrogen and water, both harmless gases.
Use low sulfur diesel fuel
Both the EPA and the Tier IV engines need ultra low sulfur diesel (ULSD), which includes only 15 parts per million of sulfur. Using non-ULSD fuel can lead to serious damage to your machine’s fuel system, DPF, or exhaust after treatment system. It can also result in potential fines or penalties from the EPA. Ultra low sulfur diesel can be found at most fueling stations.
Choose the correct oil for Tier IV engines
The transition to Tier IV engines has altered the type of engine oil that your equipment needs. You should now be using CJ4 oils, as they are engineered specifically to be compatible with aftertreatment systems while ensuring the usual performance and service intervals that you’re used to.
Using older or incorrect oil can lead to costly damage to your machine’s emissions components. To avoid accidentally using older oil with new equipment, we recommend switching all your machines, Tier IV and otherwise, to CJ4 oils. They won’t harm the older machines, and using just one type of oil will avoid any confusion.
Maintain your DPF
Most diesel particulate filters (DPFs) are made to last for at least 3,000 to 3,500 hours. The DPF is cleaned through a regeneration process that occurs while the filter is on the machine. When it comes time to replace it, read your owner’s manual to determine its exact location on your specific piece of equipment.
Don’t forget about DEF
Refilling the diesel exhaust fluid (DEF) tank must be incorporated into a routine maintenance or refueling schedule. Pieces of equipment that use DEF will have a DEF gauge and a warning signal when the level is low, similar to a fuel gauge. Always be proactive about checking the fluid levels, and change the supply module filter at the interval suggested by the manufacturer.