Tier 4 Criteria Pollutant Standards, Part 1: Phase-In Schedule for Light-Duty and Medium-Duty Vehicles

Ford Motor Company supports the EPA's proposed revisions to the Tier 4 criteria pollutant standards, specifically endorsing the addition of NMOG+NOx bins and the continued use of a Tier 3 Averaging, Banking, and Trading fleet. The company also advocates for regulatory flexibility regarding California OBD requirements and highlights technical challenges related to gasoline particulate filter back pressure.

The Alliance for Automotive Innovation supports the EPA's proposal to extend the Tier 3 emissions program and delay the implementation of Tier 4 standards. They argue that the current EV market growth is slower than anticipated and that manufacturers need more lead time to develop the necessary technologies to meet the more stringent Tier 4 requirements.

The Alliance for Automotive Innovation supports the EPA's proposal to extend the Tier 3 emissions program and delay the implementation of Tier 4 standards. They argue that the current EV market growth is slower than anticipated and that manufacturers need more lead time to develop the necessary technologies to meet the more stringent Tier 4 requirements.

General Motors supports the EPA's proposed amendments to the Tier 4 Criteria Pollutant Standards for light- and medium-duty vehicles. The company argues that the proposal appropriately reflects market realities regarding EV sales and provides necessary flexibilities for emissions standards and certification procedures.

CZV, Inc. (Czinger Vehicles), a small volume manufacturer of hypercars, supports the EPA's proposal to delay the Tier 4 criteria pollutant standards. The company argues that the delay provides necessary development time for small manufacturers and notes that their low-volume production has a negligible impact on air quality.

The Prime Mover Institute supports the EPA's proposal to delay the implementation of Tier 4 criteria-pollutant standards for light- and medium-duty vehicles due to the collapse of previous electric vehicle market projections. However, the Institute argues that the proposed two-year delay is insufficient and urges the EPA to extend the Tier 3 bridge through model year 2029 to provide manufacturers with adequate lead time.

The American Fuel & Petrochemical Manufacturers (AFPM) supports the EPA's proposal to delay the Tier 4 phase-in for light- and medium-duty vehicles through model years 2027 and 2028. They argue that the original schedule was based on inaccurate assumptions regarding battery-electric vehicle penetration and that the delay is necessary to ensure technological feasibility and adequate lead time for manufacturers.

The American Petroleum Institute (API), a national trade association representing the oil and natural gas industry, supports the proposed two-year delay of the Tier 4 criteria pollutant standards. They argue that the delay provides necessary time for manufacturers to adapt to standards that currently require electric vehicles and advocate for a more technology-neutral, cost-effective approach to emissions reductions.

Porsche Cars North America supports the EPA's proposal to delay the Tier 4 criteria pollutant standards by three years to allow for a reassessment of technical and market assumptions. The company argues that the current timeline is impractical due to slower-than-expected electric vehicle adoption and requests specific adjustments to testing procedures, vehicle classifications, and fuel specifications.

The Heritage Foundation supports the EPA's proposal to delay the Tier 4 criteria pollutant standards for light-duty and medium-duty vehicles due to market realities and technological infeasibility. They argue that the EPA should go further by extending the delay through model year 2029, removing certain On Board Diagnostic requirements, and updating economic analyses to reflect rising material costs and performance losses.