A timer-based strategy was used by seven heavy truck manufacturers, Caterpillar Inc., Cummins Engine Company, Detroit Diesel Corporation, Mack Trucks, Navistar International, Renault Véhicules Industriels, and Volvo Trucks, who in 1998 paid the largest ever fine to date, $83.4 million, for, in the same manner as Volkswagen, programming trucks to keep emissions low during the test cycle, and then disabling the controls and emitting up to three times the maximum during normal highway driving. The goal of both the Ford and the heavy truck defeat devices was better fuel economy than could be achieved under pollution limits. The major truck manufacturers also had to spend up to $1 billion to correct the problem, which affected 1.3 million heavy duty diesel trucks. While Volkswagen's actions have precedents, the Center for Auto Safety's Clarence Ditlow said that Volkswagen "took it to another level of sophisticated deception we've never seen before." In May 2017, the 28 EU member states agreed to begin negotiations with EU institutions to revise the method of testing vehicle emissions towards real circumstances, with random testing of vehicles on the roads and fines for manufacturers who breach the rules. Eben Moglen has suggested in 2010 to make proprietary software source code in general accessible to the public, to curb cheating.