Navistar recalls engines due to excessive NOx emissions

25 June 2013

In May 2013, Navistar began recalling some 4,400 trucks that “exceed pollution standards for nitrogen oxides”, said the US Environmental Protection Agency (EPA). The affected models include 2011, 2012, 2013 and 2014 model year International trucks equipped with the 2010, 2011 and 2012 model year Navistar MaxForce 11 liter diesel engine. It is a 50 state recall that also includes California models.

Navistar was required to recall some of the 2012 MY engines because they exceeded a limit established for engines certified under the EPA nonconformance penalty (NCP) rule. Navistar agreed to recall the remaining engines, produced using Navistar NOx emission credits under the EPA emissions averaging, banking, and trading (ABT) program, because they also exceeded the applicable emission standards.

EPA adopted the NCP rule in 2012, when Navistar was running out of NOx credits for their non-SCR heavy-duty engines. Under the NCP rule, Navistar was allowed to continue selling noncompliant engines certified to NOx levels above the 0.20 g/bhp-hr standard upon payment of a penalty for each engine. The NCP rule, however, included a maximum NOx cap of 0.50 g/bhp-hr. An equivalent upper limit for NOx was also included in the ABT program.

Navistar developed a revised emission software calibration for the affected engines and mailed notification letters to truck owners advising them to contact a dealership to upgrade their engine software. Navistar has indicated that the recall will not harm fuel economy.

Source: US EPA