Truckers Expose Flaws in EPA Emissions Fix

The U.S. Environmental Protection Agency is reviewing more than 13,500 public comments on proposed changes to heavy-duty truck emissions requirements, including how vehicles respond when diesel exhaust fluid levels or systems fall out of compliance. The agency could issue a revised final rule, but the timeline for completing the process is narrowing.

OOIDA seeks changes to DEF warnings

The Owner-Operator Independent Drivers Association said truck operators need a clearer warning system when a DEF-related problem occurs. Under the group’s recommendation, an audible alert would give drivers time to address the issue safely without immediately facing severe speed reductions, missed deliveries or extended downtime.

DEF, or diesel exhaust fluid, is used in selective catalytic reduction systems to reduce nitrogen oxide emissions from modern diesel engines. Trucks can experience operating restrictions, commonly known as inducements, when DEF runs low or when the emissions-control system detects a fault.

OOIDA said a more practical warning process could help drivers correct problems before the vehicle is significantly restricted. The organization has argued that current inducement procedures can create operational and financial challenges for small carriers and independent truck owners.

Retailers and industry groups raise concerns

The National Association of Convenience Stores has also urged the EPA to maintain the current DEF framework. More than 100,000 retail locations across North America sell DEF, including more than 95% of North American truck stops, according to the organization.

NACS Deputy General Counsel Matt Durand said the agency should allow existing guidance to take effect before making additional changes. The group also warned that changes suggesting DEF is optional could reduce compliance and weaken demand for the product.

Other industry stakeholders have raised concerns about the potential impact of the proposal on emissions performance. Critics contend that easing DEF-related requirements could result in higher nitrogen oxide pollution if drivers or fleets delay repairs or fail to maintain emissions systems.

Proposal would affect future truck standards

The proposed revisions would apply to heavy-duty vehicles, including tractor-trailers, work trucks and dump trucks. The plan would also establish non-conformance penalties, allowing manufacturers to pay penalties when vehicles do not meet certain requirements, according to critics of the proposal.

The proposal could shorten the emissions warranty period and the vehicle’s “useful life,” or the period during which it must continue meeting applicable pollution standards. Environmental and public-health advocates have argued that those changes could increase emissions near highways, freight corridors and other communities with heavy truck traffic.

The EPA’s analysis, as cited by opponents, found that the proposed rollback could result in additional harmful air pollution even without fully accounting for the effects of removing or reducing DEF inducements.

EPA review continues

Engine manufacturers have emphasized that the underlying EPA27 emissions standard remains significantly more stringent than current requirements. PACCAR Senior Director of Powertrain Planning Carl Hergart said the proposed limit of 0.035 grams of nitrogen oxides per horsepower-hour would represent more than an 80% reduction from the current standard.

With the public comment period closed, the EPA must review the submissions before deciding whether to finalize, revise or withdraw portions of the proposal. The final outcome could affect truck manufacturers, fleets, independent operators, DEF retailers and the maintenance requirements for future heavy-duty vehicles.