GM cut its warranty and goodwill costs by 20 percent between 1999 and 2004. Since 1999, the number of warranty cases has fallen 65 percent. The company isn't releasing figures on annual expenditures.
GM Europe ultimately wants to halve warranty costs related to durability in the next three years, said Peter Dersley, GM Europe vice president of quality.
GM Europe's improvements are the result of a quality initiative launched in the late 1990s.
Dersley said that since Opel started addressing quality issues, supplier defects have declined 80 percent. He said that Opel rejects just 70 supplier parts per million today, down from 350 five years ago.
Still, when compared with other sectors, he said GM Europe and the entire auto industry have the potential for further improvement.