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Tier 4 Locomotives

Tier 4 Locomotive | Clean Power

Tier 4 Locomotive

Metrolink is continuing its tradition as a transportation leader by upgrading its fleet of locomotives to become the first passenger railroad in the nation to use locomotives with Tier 4 clean technology. Tier 4 locomotives reduce emissions between 65% and 85% compared to legacy Tier 2 and Tier 0 locomotives in Metrolink’s fleet. Tier 4 locomotives began phasing into service in fall 2017.


Metrolink’s investment in Tier 4 technology will result in cleaner air for the entire region. The state-of-the-art Tier 4 locomotives are the cleanest diesel locomotives in the nation, providing wide-ranging environmental benefits for the Southern California region. Tier 4 locomotives are compliant with the latest U.S. Environmental Protection Agency (EPA) emissions standards and will reduce particulate matter and nitrogen oxide emissions by up to 85 percent compared to older locomotives.

Metrolink Tier 4 Locomotive

Tier 4 locomotive undergoing testing


Metrolink’s Tier 4 engines are more powerful with up to 64 percent more horsepower than Tier 0 locomotives.

Safety is the top consideration and highest priority at Metrolink. As such, Tier 4 locomotives are equipped with the newest rail safety technology, including PTC and crash energy management technology.

The back of a Tier 4 locomotive

Tier 4 includes the latest safety features


Metrolink’s acquisition of Tier 4 locomotives is a true joint effort and would not be possible without the support of our partners, including the South Coast Air Quality Management District (SCAQMD), our member agencies: Los Angeles County Metropolitan Transportation Authority (METRO), Orange County Transportation Authority (OCTA), Riverside County Transportation Commission (RCTC), San Bernardino County Transportation Authority (SBCTA), and Ventura County Transportation Commission (VCTC), elected officials and our community members.

Join Metrolink and our partners as we lead the Southern California region into a cleaner, safer and more reliable future in transportation.


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Tier 4 Locomotive Tier 4 Locomotive Tier 4 Locomotive

Tier 4 Locomotive Tier 4 Locomotive Tier 4 Locomotive

Special thanks to: California Air Resource Board, South Coast AQMD, CalSTA,Caltrans, California Transportation Commission, Metro, OCTA,RCTC,VCTC, and SANBAG