The Tier 4 requirement, which took effect for 2008 model-year engines, reduces particulate matter output by 50 percent - down to 0.4 grams per kilowatt-hour, compared to the previous standard. The engines used on Supra units reduce the output an additional 40 percent. Depending on the model, they also reduce emissions of combined nitrogen oxides and hydrocarbons by 12 to 17 percent below the Tier 4 requirement.
Tier 4 engines are now standard issue for the Supra 550, 650, 750, 850 and 950, as well as Genesis R-90 units.
For trucks driven in California, the Tier 4 units comply with applicable CARB requirements. Additionally, for model year 2001 and older Supra units used in California that need to be "emission enhanced" for compliance with CARB this year, the Tier 4 engines can be used as replacements for older engines.
Supra units with the electric standby option can be plugged into an electrical supply at loading docks equipped with power drops with proper CARB documentation. Using the standby mode, engines can be shut down when parked, eliminating emissions, noise and fuel consumption.
More info: www.trucktrailer.carrier.com