But staying on top will be a challenge for the German maker of the Golf and Polo, as deliveries are falling in China, destination of a third of its global sales, making it overly reliant on relatively stagnant western European demand.
"The hunt for scale only makes sense if it boosts synergies, something VW hasn't really been able to achieve," said Stefan Bratzel, head of the Center of Automotive Management think-tank. "Dependence on China is VW's weak spot and managing such a large group inevitably poses problems."
The German group on July 17 reported 5.04 million deliveries in the first half year. By comparison, Toyota said on Tuesday it sold 5.02 million cars between January and June, a 1.5 percent decline on year-ago levels.
Toyota, due to announce first-half earnings next Tuesday, said sales were dragged down by a slowdown in emerging markets and increased taxes on mini vehicles in Japan.
VW's rapid expansion has masked underperformance in the United States and Brazil, where it has been slow to upgrade models and adjust its offerings to market trends, analysts say.
With over 310 models and nearly 120 factories worldwide, VW's size may be turning into a disadvantage, forming the backdrop to a leadership crisis in April when ex-chairman Ferdinand Piech was ousted after publicly criticizing CEO Winterkorn.
Wolfsburg-based VW last year started shifting its focus to boosting earnings quality to help fund growing technology needs and plant upgrades.
VW has a goal of "moderately" raising deliveries from last year's record 10.14 million cars. The group will publish first-half results on Wednesday. ($1 = 0.9042 euros)
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