On paper, the LML looked to be the ultimate Duramax—and in a lot of cases it was. Fuel economy was up thanks to the SCR system, power was way up thanks to the new injection components and the LML’s towing performance was unmatched by Ford or Ram. However,injection pump problemstended...
A large percentage of 2011 model year 6.6L Duramax LML diesels endured repeated reliability problems with the SCR and DEF systems. The DEF sensor, NOx sensor, and DEF pump are amongst the most commonly replaced components of the system. Additionally, problems were identified with DEF freezing in...