Automakers tend to jealously guard their market share because once it's gone, it can be extremely difficult to win back.
Yet with the microchip shortage stirring the sales race this year, a question is starting to emerge: If Toyota Motor North America and Hyundai-Kia keep picking up market share as they have this year because they have vehicles to sell and others don't, are they, with their high customer retention rates, likely to give it back when inventories normalize?
Toyota not only leads General Motors in overall sales through the first three quarters but also has picked up 1.8 percentage points of U.S. market share over the last year. It now leads the industry, at 15.8 percent. Hyundai-Kia's market share has also climbed dramatically over the last 12 months, rising 1.5 percentage points to 10 percent, tying it with American Honda. Meanwhile, Ford Motor Co.'s market share has fallen 2.6 percentage points to 11.8 percent, GM has lost 2 ful…