By William Boston
Updated Dec. 10, 2014 9:50 p.m. ET
Volkswagen, after all, is on track to sell more than 10 million cars and trucks in 2014—four years ahead of plan. It overtook GM last year and could soon eclipse Toyota to claim the industry’s top spot.
But on Tuesday, Mr. Winterkorn surprised investors by announcing he would step down as CEO of the VW brand, the company’s namesake marque which has suffered dwindling sales in most markets as well as weak overall profits. He will retain his position as group CEO. His replacement at the VW unit, a top executive from German rival BMW AG , Herbert Diess, will come aboard in October.