the public notice and an opportunity for comment. In the meantime, Navistar's EGR decision had led to significant reliability issues and quality problems (which were ultimately traceable to the fundamental physical reality that recirculation of exhaust gas introduces intrinsically abrasive soot and inherently corrosive acid gases back into the engine). Truck drivers began losing trust and confidence as Navistar vehicles were breaking down frequently. Consequently, they abandoned Navistar trucks in favor of competitor's trucks. Legal issues (MaxxForce engines) In December 2014, the United States Judicial Panel on Multidistrict Litigation ordered that 13 of 14 civil lawsuits brought against Navistar for MaxxForce engines would be consolidated into one case. The consolidated lawsuits say Navistar's use of Advanced Exhaust Gas Recirculation emission control system, or EGR, was defective and resulted in repeated engine failures and frequent repairs and downtime. On December 16, 2014, Navistar reported a larger than expected fourth quarter net loss of $72 million. While sales rose 9 percent to $3 billion, the company cited restructuring and warranty costs as the main reasons for the loss. A day earlier, the company announced it would be closing its engine foundry in Indianapolis, resulting in the loss of 100 jobs and costing $11 million. The company estimated annual savings of $13 million in operating costs. In March 2015, Navistar reported a first-quarter 2015 net loss of $42 million, or $0.52 per diluted share, compared to a first-quarter 2014 net loss of $248 million, or $3.05 per diluted share. Revenues in the quarter were $2.4 billion, up to $213 million or 10 percent, versus the first quarter of 2014. The higher revenues in the quarter were driven by a 17 percent year-over-year increase in charge outs for Class 6-8 trucks and buses in the United States and Canada. This included a 42 percent increase in school buses; a 25 percent increase in Class 6/7 medium trucks; a 7 percent increase in Class 8 heavy trucks; and a 5 percent increase in Class 8 severe service trucks. Higher sales in the company's export truck operations also contributed to the increase, partially offset by a decrease in used truck sales. The company finished the first quarter with a 27 percent year-over-year increase in order backlog for Class 6-8 trucks. On June 4, 2015, Navistar reported a second-quarter net loss of $64 million, or 78 cents a share, compared with a year-earlier loss of $297 million,