
America's Environmental Protection Agency last week filed a lawsuit against Navistar International Corporation for alleged breaches of that country's Clean Air Act, relating to the sale of heavy-duty trucks sold in 2010 that failed to comply with emissions regulations.
Navistar has said the engines concerned – said to number 7750 units – were built in 2009 but finished in early 2010, and that the company complied with the appropriate regulations of the time.
New EPA emissions regulations were brought into effect from January 1, 2010.
The lawsuit is believed to be seeking penalties of up to $37,500 per day for each violation of the regulations which, given the number of engines in doubt, could potentially add up to a fine of around $US300 million.
According to a report in the Wall Street Journal, Navistar claims the engines at fault should be permitted as "transitory" units able to be used in 2010-built vehicles, but the EPA claims the maker never sought the appropriate exemptions.
Competitor brands, meanwhile, have said that Navistar's use of the engines allowed it to sell 2010-plated trucks at a significantly lower price, as the trucks didn't feature the expensive emissions technology required to meet the new standards.